# EDGAR Filing Document

**Accession Number:** 0000916053
**File Stem:** 0001104659-23-009766
**Filing Date:** 2023-2
**Character Count:** 1198703
**Document Hash:** 834789f73a22ffb2ce5535bac132c307
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-23-009766.hdr.sgml**: 20230202

**ACCESSION NUMBER**: 0001104659-23-009766

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 26

**FILED AS OF DATE**: 20230202

**DATE AS OF CHANGE**: 20230202

**EFFECTIVENESS DATE**: 20230202

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MASSMUTUAL SELECT FUNDS
- **CENTRAL INDEX KEY:** 0000916053
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0930

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-73824
- **FILM NUMBER:** 23579676

**BUSINESS ADDRESS:**
- **STREET 1:** 1295 STATE STREET
- **CITY:** SPRINGFIELD
- **STATE:** MA
- **ZIP:** 01111
- **BUSINESS PHONE:** 413-744-1000

**MAIL ADDRESS:**
- **STREET 1:** 1295 STATE STREET
- **CITY:** SPRINGFIELD
- **STATE:** MA
- **ZIP:** 01111

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MASSMUTUAL INSTITUTIONAL FUNDS
- **DATE OF NAME CHANGE:** 19931213

## Series and Classes Contracts Data

### MassMutual RetireSMART by JPMorgan 2020 Fund (Series ID: S000003675)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MRTAX         | C000010262 |
| Class R3             | MRTNX         | C000010264 |
| Service Class        | MRTSX         | C000010265 |
| Administrative Class | MRTYX         | C000010266 |
| Class I              | MRTDX         | C000140371 |
| Class R5             | MRTBX         | C000140372 |
| Class R4             | MRTHX         | C000140373 |

---

### MassMutual RetireSMART by JPMorgan 2030 Fund (Series ID: S000003676)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MRYAX         | C000010267 |
| Class R3             | MRYNX         | C000010269 |
| Service Class        | MRYSX         | C000010270 |
| Administrative Class | MRYYX         | C000010271 |
| Class I              | MRYUX         | C000140374 |
| Class R5             | MRYTX         | C000140375 |
| Class R4             | MRYZX         | C000140376 |

---

### MassMutual RetireSMART by JPMorgan 2040 Fund (Series ID: S000003677)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MRFAX         | C000010272 |
| Class R3             | MFRNX         | C000010274 |
| Service Class        | MFRSX         | C000010275 |
| Administrative Class | MRFYX         | C000010276 |
| Class I              | MRFUX         | C000140377 |
| Class R5             | MRFTX         | C000140378 |
| Class R4             | MRFZX         | C000140379 |

---

### MassMutual RetireSMART by JPMorgan In Retirement Fund (Series ID: S000003678)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MRDAX         | C000010277 |
| Class R3             | MDRNX         | C000010279 |
| Service Class        | MDRSX         | C000010280 |
| Administrative Class | MDRYX         | C000010281 |
| Class I              | MDRVX         | C000140380 |
| Class R5             | MDRTX         | C000140381 |
| Class R4             | MDRZX         | C000140382 |

---

### MassMutual RetireSMART by JPMorgan 2050 Fund (Series ID: S000020009)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class R3             | MMRNX         | C000056105 |
| Service Class        | MMTSX         | C000056106 |
| Administrative Class | MMRYX         | C000056107 |
| Class A              | MMARX         | C000056109 |
| Class I              | MMRUX         | C000140393 |
| Class R5             | MMRTX         | C000140394 |
| Class R4             | MMRZX         | C000140395 |

---

### MassMutual RetireSMART by JPMorgan 2025 Fund (Series ID: S000028351)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MMSDX         | C000086630 |
| Service Class        | MMISX         | C000086632 |
| Administrative Class | MMIYX         | C000086633 |
| Class I              | MMNUX         | C000140403 |
| Class R5             | MMNTX         | C000140404 |
| ClassR4              | MMNZX         | C000140405 |
| Class R3             | MMNRX         | C000140406 |

---

### MassMutual RetireSMART by JPMorgan 2035 Fund (Series ID: S000028352)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MMXAX         | C000086634 |
| Service Class        | MMXSX         | C000086636 |
| Administrative Class | MMXYX         | C000086637 |
| Class I              | MMXUX         | C000140407 |
| Class R5             | MMXTX         | C000140408 |
| Class R4             | MMXZX         | C000140409 |
| Class R3             | MMXNX         | C000140410 |

---

### MassMutual RetireSMART by JPMorgan 2045 Fund (Series ID: S000028353)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class A              | MMKAX         | C000086639 |
| Service Class        | MMKSX         | C000086641 |
| Administrative Class | MMKYX         | C000086642 |
| Class I              | MMKUX         | C000140411 |
| Class R5             | MMKTX         | C000140412 |
| Class R4             | MMKZX         | C000140413 |
| Class R3             | MMKNX         | C000140414 |

---

### MassMutual 20/80 Allocation Fund (Series ID: S000032893)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class R5             | MRCSX         | C000101523 |
| Service Class        | MRCYX         | C000101524 |
| Administrative Class | MRCLX         | C000101525 |
| Class A              | MCTAX         | C000101526 |
| Class I              | MRCUX         | C000140416 |
| Class R4             | MRCZX         | C000140417 |
| Class R3             | MRCVX         | C000140418 |
| Class Y              | nan           | C000240801 |

---

### MassMutual 40/60 Allocation Fund (Series ID: S000032894)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class R5             | MROSX         | C000101527 |
| Service Class        | MRMYX         | C000101528 |
| Administrative Class | MRMLX         | C000101529 |
| Class A              | MRMAX         | C000101530 |
| Class I              | MRMUX         | C000140419 |
| Class R4             | MRMZX         | C000140420 |
| Class R3             | MRMTX         | C000140421 |
| Class Y              | nan           | C000240802 |

---

### MassMutual 60/40 Allocation Fund (Series ID: S000032895)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Service Class        | MROYX         | C000101531 |
| Administrative Class | MRSLX         | C000101532 |
| Class A              | MOGAX         | C000101533 |
| Class R5             | MRSSX         | C000101534 |
| Class I              | MROUX         | C000140422 |
| Class R4             | MROZX         | C000140423 |
| Class R3             | MROTX         | C000140424 |
| Class Y              | nan           | C000240803 |

---

### MassMutual 80/20 Allocation Fund (Series ID: S000032896)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class R5             | MRRSX         | C000101535 |
| Service Class        | MRGYX         | C000101536 |
| Administrative Class | MRGLX         | C000101537 |
| Class A              | MRRAX         | C000101538 |
| Class I              | MRGUX         | C000140425 |
| Class R4             | MRGZX         | C000140426 |
| Class R3             | MRGVX         | C000140427 |
| Class Y              | nan           | C000240804 |

---

### MassMutual RetireSMART by JPMorgan 2055 Fund (Series ID: S000042052)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Service Class        | MMWSX         | C000130636 |
| Administrative Class | MMWYX         | C000130637 |
| Class A              | MMWAX         | C000130639 |
| Class I              | MMWZX         | C000140434 |
| Class R5             | MMWUX         | C000140435 |
| Class R4             | MMWEX         | C000140436 |
| Class R3             | MMWTX         | C000140437 |

---

### MassMutual RetireSMART by JPMorgan 2060 Fund (Series ID: S000051694)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Class I              | MMWIX         | C000162675 |
| Class R5             | MMWHX         | C000162676 |
| Service Class        | MMWGX         | C000162677 |
| Administrative Class | MMWFX         | C000162678 |
| Class A              | MMWDX         | C000162679 |
| Class R4             | MMWCX         | C000162680 |
| Class R3             | MMWBX         | C000162681 |

---

### MassMutual RetireSMART by JPMorgan 2065 Fund (Series ID: S000079614)

---

|  |  |
|:---|:---|
| Class Name           | Class ID   |
| Class R3             | C000240776 |
| Class I              | C000240777 |
| Class A              | C000240778 |
| Class R4             | C000240779 |
| Class R5             | C000240780 |
| Service Class        | C000240781 |
| Administrative Class | C000240782 |

---

## Series and Classes Contracts Data

### MassMutual RetireSMART by JPMorgan 2020 Fund (Series ID: S000003675)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000010262 | Class A              | MRTAX           |
| C000010264 | Class R3             | MRTNX           |
| C000010265 | Service Class        | MRTSX           |
| C000010266 | Administrative Class | MRTYX           |
| C000140371 | Class I              | MRTDX           |
| C000140372 | Class R5             | MRTBX           |
| C000140373 | Class R4             | MRTHX           |

### MassMutual RetireSMART by JPMorgan 2030 Fund (Series ID: S000003676)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000010267 | Class A              | MRYAX           |
| C000010269 | Class R3             | MRYNX           |
| C000010270 | Service Class        | MRYSX           |
| C000010271 | Administrative Class | MRYYX           |
| C000140374 | Class I              | MRYUX           |
| C000140375 | Class R5             | MRYTX           |
| C000140376 | Class R4             | MRYZX           |

### MassMutual RetireSMART by JPMorgan 2040 Fund (Series ID: S000003677)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000010272 | Class A              | MRFAX           |
| C000010274 | Class R3             | MFRNX           |
| C000010275 | Service Class        | MFRSX           |
| C000010276 | Administrative Class | MRFYX           |
| C000140377 | Class I              | MRFUX           |
| C000140378 | Class R5             | MRFTX           |
| C000140379 | Class R4             | MRFZX           |

### MassMutual RetireSMART by JPMorgan In Retirement Fund (Series ID: S000003678)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000010277 | Class A              | MRDAX           |
| C000010279 | Class R3             | MDRNX           |
| C000010280 | Service Class        | MDRSX           |
| C000010281 | Administrative Class | MDRYX           |
| C000140380 | Class I              | MDRVX           |
| C000140381 | Class R5             | MDRTX           |
| C000140382 | Class R4             | MDRZX           |

### MassMutual RetireSMART by JPMorgan 2050 Fund (Series ID: S000020009)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000056105 | Class R3             | MMRNX           |
| C000056106 | Service Class        | MMTSX           |
| C000056107 | Administrative Class | MMRYX           |
| C000056109 | Class A              | MMARX           |
| C000140393 | Class I              | MMRUX           |
| C000140394 | Class R5             | MMRTX           |
| C000140395 | Class R4             | MMRZX           |

### MassMutual RetireSMART by JPMorgan 2025 Fund (Series ID: S000028351)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000086630 | Class A              | MMSDX           |
| C000086632 | Service Class        | MMISX           |
| C000086633 | Administrative Class | MMIYX           |
| C000140403 | Class I              | MMNUX           |
| C000140404 | Class R5             | MMNTX           |
| C000140405 | ClassR4              | MMNZX           |
| C000140406 | Class R3             | MMNRX           |

### MassMutual RetireSMART by JPMorgan 2035 Fund (Series ID: S000028352)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000086634 | Class A              | MMXAX           |
| C000086636 | Service Class        | MMXSX           |
| C000086637 | Administrative Class | MMXYX           |
| C000140407 | Class I              | MMXUX           |
| C000140408 | Class R5             | MMXTX           |
| C000140409 | Class R4             | MMXZX           |
| C000140410 | Class R3             | MMXNX           |

### MassMutual RetireSMART by JPMorgan 2045 Fund (Series ID: S000028353)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000086639 | Class A              | MMKAX           |
| C000086641 | Service Class        | MMKSX           |
| C000086642 | Administrative Class | MMKYX           |
| C000140411 | Class I              | MMKUX           |
| C000140412 | Class R5             | MMKTX           |
| C000140413 | Class R4             | MMKZX           |
| C000140414 | Class R3             | MMKNX           |

### MassMutual 20/80 Allocation Fund (Series ID: S000032893)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000101523 | Class R5             | MRCSX           |
| C000101524 | Service Class        | MRCYX           |
| C000101525 | Administrative Class | MRCLX           |
| C000101526 | Class A              | MCTAX           |
| C000140416 | Class I              | MRCUX           |
| C000140417 | Class R4             | MRCZX           |
| C000140418 | Class R3             | MRCVX           |
| C000240801 | Class Y              |  |

### MassMutual 40/60 Allocation Fund (Series ID: S000032894)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000101527 | Class R5             | MROSX           |
| C000101528 | Service Class        | MRMYX           |
| C000101529 | Administrative Class | MRMLX           |
| C000101530 | Class A              | MRMAX           |
| C000140419 | Class I              | MRMUX           |
| C000140420 | Class R4             | MRMZX           |
| C000140421 | Class R3             | MRMTX           |
| C000240802 | Class Y              |  |

### MassMutual 60/40 Allocation Fund (Series ID: S000032895)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000101531 | Service Class        | MROYX           |
| C000101532 | Administrative Class | MRSLX           |
| C000101533 | Class A              | MOGAX           |
| C000101534 | Class R5             | MRSSX           |
| C000140422 | Class I              | MROUX           |
| C000140423 | Class R4             | MROZX           |
| C000140424 | Class R3             | MROTX           |
| C000240803 | Class Y              |  |

### MassMutual 80/20 Allocation Fund (Series ID: S000032896)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000101535 | Class R5             | MRRSX           |
| C000101536 | Service Class        | MRGYX           |
| C000101537 | Administrative Class | MRGLX           |
| C000101538 | Class A              | MRRAX           |
| C000140425 | Class I              | MRGUX           |
| C000140426 | Class R4             | MRGZX           |
| C000140427 | Class R3             | MRGVX           |
| C000240804 | Class Y              |  |

### MassMutual RetireSMART by JPMorgan 2055 Fund (Series ID: S000042052)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000130636 | Service Class        | MMWSX           |
| C000130637 | Administrative Class | MMWYX           |
| C000130639 | Class A              | MMWAX           |
| C000140434 | Class I              | MMWZX           |
| C000140435 | Class R5             | MMWUX           |
| C000140436 | Class R4             | MMWEX           |
| C000140437 | Class R3             | MMWTX           |

### MassMutual RetireSMART by JPMorgan 2060 Fund (Series ID: S000051694)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000162675 | Class I              | MMWIX           |
| C000162676 | Class R5             | MMWHX           |
| C000162677 | Service Class        | MMWGX           |
| C000162678 | Administrative Class | MMWFX           |
| C000162679 | Class A              | MMWDX           |
| C000162680 | Class R4             | MMWCX           |
| C000162681 | Class R3             | MMWBX           |

### MassMutual RetireSMART by JPMorgan 2065 Fund (Series ID: S000079614)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000240776 | Class R3             |  |
| C000240777 | Class I              |  |
| C000240778 | Class A              |  |
| C000240779 | Class R4             |  |
| C000240780 | Class R5             |  |
| C000240781 | Service Class        |  |
| C000240782 | Administrative Class |  |

[**TABLE OF CONTENTS**](#TOC)

### MASSMUTUAL FUNDS
This Prospectus describes the following Funds:

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| **Fund Name**  | &nbsp;&nbsp; **Class I**  | **Class R5**  | &nbsp;&nbsp;&nbsp; **Service<br>Class**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Administrative<br>Class**  | **Class R4**  | &nbsp;&nbsp; **Class A**  | **Class R3**  | **Class Y**  |
| MassMutual 20/80 Allocation Fund  | MRCUX  | MRCSX  | MRCYX  | MRCLX  | MRCZX  | MCTAX  | MRCVX  | MMNOX |
| MassMutual 40/60 Allocation Fund  | MRMUX  | MROSX  | MRMYX  | MRMLX  | MRMZX  | MRMAX  | MRMTX  | MMNPX |
| MassMutual 60/40 Allocation Fund  | MROUX  | MRSSX  | MROYX  | MRSLX  | MROZX  | MOGAX  | MROTX  | MMNQX |
| MassMutual 80/20 Allocation Fund  | MRGUX  | MRRSX  | MRGYX  | MRGLX  | MRGZX  | MRRAX  | MRGVX  | MMNSX |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan In Retirement Fund  | MDRVX  | MDRTX  | MDRSX  | MDRYX  | MDRZX  | MRDAX  | MDRNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2020 Fund  | MRTDX  | MRTBX  | MRTSX  | MRTYX  | MRTHX  | MRTAX  | MRTNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2025 Fund  | MMNUX  | MMNTX  | MMISX  | MMIYX  | MMNZX  | MMSDX  | MMNRX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2030 Fund  | MRYUX  | MRYTX  | MRYSX  | MRYYX  | MRYZX  | MRYAX  | MRYNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2035 Fund  | MMXUX  | MMXTX  | MMXSX  | MMXYX  | MMXZX  | MMXAX  | MMXNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2040 Fund  | MRFUX  | MRFTX  | MFRSX  | MRFYX  | MRFZX  | MRFAX  | MFRNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2045 Fund  | MMKUX  | MMKTX  | MMKSX  | MMKYX  | MMKZX  | MMKAX  | MMKNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2050 Fund  | MMRUX  | MMRTX  | MMTSX  | MMRYX  | MMRZX  | MMARX  | MMRNX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2055 Fund  | MMWZX  | MMWUX  | MMWSX  | MMWYX  | MMWEX  | MMWAX  | MMWTX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2060 Fund  | MMWIX  | MMWHX  | MMWGX  | MMWFX  | MMWCX  | MMWDX  | MMWBX  |  |
|  MassMutual RetireSMART<sup>SM</sup> <br> by JPMorgan 2065 Fund  | MMZBX | MMZCX | MMZDX | MMZEX | MMZFX | MMZGX | MMZHX |  |

---

**The Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any statement to the contrary is a crime.**

#### PROSPECTUS
February 1, 2023

As Revised on February 2, 2023

------

[**TABLE OF CONTENTS**](#TOC)

### Table Of Contents

---

| | |
|:---|:---|
| | **Page**  |
| **About the Funds** | **About the Funds** |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual 20/80 Allocation Fund](#idMM2080AF104122)  | [3](#idMM2080AF104122) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual 40/60 Allocation Fund](#idMM4060AF103925)  | [13](#idMM4060AF103925) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual 60/40 Allocation Fund](#idMM6040AF103895)  | [23](#idMM6040AF103895) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual 80/20 Allocation Fund](#idMM8020AF103471)  | [33](#idMM8020AF103471) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan In Retirement Fund](#idMMRSMARTSMJ101893)  | [43](#idMMRSMARTSMJ101893) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2020 Fund](#idMMRSMARTSMJ116257)  | [53](#idMMRSMARTSMJ116257) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2025 Fund](#idMMRSMARTSMJ116008)  | [66](#idMMRSMARTSMJ116008) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2030 Fund](#idMMRSMARTSMJ115909)  | [79](#idMMRSMARTSMJ115909) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2035 Fund](#idMMRSMARTSMJ116319)  | [92](#idMMRSMARTSMJ116319) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2040 Fund](#idMMRSMARTSMJ115647)  | [105](#idMMRSMARTSMJ115647) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2045 Fund](#idMMRSMARTSMJ116027)  | [118](#idMMRSMARTSMJ116027) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2050 Fund](#idMMRSMARTSMJ116019)  | [131](#idMMRSMARTSMJ116019) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2055 Fund](#idMMRSMARTSMJ116086)  | [144](#idMMRSMARTSMJ116086) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2060 Fund](#idMMRSMARTSMJ115800)  | [157](#idMMRSMARTSMJ115800) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2065 Fund](#idMMRSMARTSMJ103789)  | [170](#idMMRSMARTSMJ103789) |
| **[Additional Information Regarding Investment Objectives and Principal Investment Strategies](#idAIRIOPIS78312)**  | **[183](#idAIRIOPIS78312)**  |
| **[Disclosure of Portfolio Holdings](#idDPH303)**  | **[190](#idDPH303)**  |
| **[Additional Information Regarding Principal Risks](#idAIRPR116508)**  | **[190](#idAIRPR116508)**  |
| **Management of the Funds** | **Management of the Funds** |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Investment Adviser and Portfolio Managers](#idIAPM4392)  | [211](#idIAPM4392) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Subadviser and Portfolio Managers](#idSPM5665)  | [211](#idSPM5665) |
| **[About the Classes of Shares – I, R5, Service, Administrative, R4, A, R3, and Y Shares](#idACSIR5SAR4A9290)**  | **[213](#idACSIR5SAR4A9290)**  |
| **[Sales Charges by Class](#idSCC14530)**  | **[215](#idSCC14530)**  |
| **[Sales Charge Waivers by Class](#idSCWC6143)**  | **[217](#idSCWC6143)**  |
| **[Distribution Plan, Shareholder Servicing, and Payments to Intermediaries](#idDPSSPI10003)**  | **[218](#idDPSSPI10003)**  |
| **[Buying, Redeeming, and Exchanging Shares](#idBRES20142)**  | **[220](#idBRES20142)**  |
| **[Cost Basis Reporting](#idCBR874)**  | **[223](#idCBR874)**  |
| **[Frequent Trading Policies](#idF2P4958)**  | **[223](#idF2P4958)**  |
| **[Determining Net Asset Value](#idDNAV2709)**  | **[224](#idDNAV2709)**  |
| **[Taxation and Distributions](#idTD9680)**  | **[226](#idTD9680)**  |
| **[Financial Highlights](#idFH994)**  | **[228](#idFH994)**  |
| **[Index Descriptions](#idID3462)**  | **[243](#idID3462)**  |

---

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MassMutual 20/80 Allocation Fund

#### INVESTMENT OBJECTIVE
The Fund seeks to achieve as high a total return over time as is considered consistent with prudent investment risk, preservation of capital and recognition of the Fund's stated asset allocation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |  |
| Other Expenses | 0.12%  | 0.22%  | 0.32%  | 0.42%  | 0.32%  | 0.42%  | 0.32%  | 0.22%<sup>(1)</sup>  |
|  Acquired Fund Fees and Expenses  | 0.42%  | 0.42%  | 0.42%  | 0.42%  | 0.42%  | 0.42%  | 0.42%  | 0.42%  |
|  **Total Annual Fund Operating Expenses<sup>(2)</sup>**  | **0.54%**  | **0.64%**  | **0.74%**  | **0.84%**  | **0.99%**  | **1.09%**  | **1.24%**  | **0.64%**  |
| Expense Reimbursement | (0.08%)  | (0.08%)  | (0.08%)  | (0.08%)  | (0.08%)  | (0.08%)  | (0.08%)  | (0.08%)  |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(3)</sup>  | 0.46%  | 0.56%  | 0.66%  | 0.76%  | 0.91%  | 1.01%  | 1.16%  | 0.56%  |

---

(1) Other Expenses are based on estimated amounts for the current fiscal year of the Fund.

(2) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(3) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.04%, 0.14%, 0.24%, 0.34%, 0.49%, 0.59%, 0.74%, and 0.14% for Classes I, R5, Service, Administrative, R4, A, R3, and Y, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $47 | $165 | $294 | $669 |
| Class R5 | $57 | $197 | $349 | $791 |
| Service Class | $67 | $229 | $404 | $911 |
|  Administrative Class  | $78 | $260 | $458 | $1030 |
| Class R4 | $93 | $307 | $539 | $1206 |
| Class A | $647 | $870 | $1110 | $1799 |
| Class R3 | $118 | $386 | $673 | $1493 |
| Class Y | $57 | $197 | $349 | $791 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 27% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers"). Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments.

The Fund typically invests approximately 20% of its assets in equity and similar funds and approximately 80% in fixed income funds, including money market funds. Under normal circumstances, the Fund's asset allocation between equity and fixed income funds is generally expected to vary by no more than plus or minus ten percentage points from this target asset allocation strategy. MML Advisers will generally attempt to select Underlying Funds that it expects will provide an aggregate exposure to "junk" or "high yield" bonds (securities rated below investment grade by Moody's or Standard & Poor's, or unrated securities determined to be of comparable quality by the applicable adviser or subadviser), including securities in default, of not more than 10% of the Fund's assets (although the Fund's exposure may from time to time exceed that percentage). The Fund is designed for use as part of an overall investment strategy by an investor who is saving for, or is already in, retirement.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers; the Fund will normally invest no more than 30% of its assets in mutual funds not advised by MML Advisers (referred to here as "non-affiliated" funds). Non-affiliated funds may include actively managed funds, or they may be passively managed funds seeking to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry. MML Advisers will select most of the Underlying Funds from among mutual funds advised by it even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers did not consider such factors or was not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, among various asset classes and Underlying Funds. MML Advisers does not intend to trade actively among

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Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers in its absolute discretion may modify the asset allocation strategy or the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

---

| | |
|:---|:---|
| ***Equity Funds*** | 20.1% |
| **— U.S. Large Cap Equity Funds** |  |
| MassMutual Fundamental Value Fund | 1.2% |
| MassMutual Diversified Value Fund  | 1.3% |
| MassMutual Equity Opportunities Fund  | 2.8% |
| MM Equity Asset Fund  | 5.1% |
| MassMutual Blue Chip Growth Fund  | 1.9% |
| MassMutual Growth Opportunities Fund  | 0.5% |
| **— U.S. Small/Mid Cap Equity Funds** |  |
| MassMutual Mid Cap Value Fund  | 0.6% |
| Vanguard Mid-Cap Index Fund | 0.8% |
| MassMutual Mid Cap Growth Fund  | 0.6% |
| MassMutual Small Cap Value Equity Fund  | 0.3% |
| Vanguard Small-Cap Index Fund  | 0.3% |
| MassMutual Small Cap Growth Equity Fund  | 0.2% |
| **— REIT Funds** |  |
| Invesco Real Estate Fund | 0.4% |
| **— International Equity Funds** |  |
| MassMutual Overseas Fund  | 1.4% |
| MassMutual International Equity Fund  | 0.7% |
| Vanguard Developed Markets Index Fund  | 1.4% |
| **— Emerging Markets Equity Funds** |  |
| MassMutual Strategic Emerging Markets Fund | 0.3% |
| Vanguard Emerging Markets Stock Index Fund  | 0.3% |
| ***Fixed Income Funds***  | 79.6% |
| **— U.S. Fixed Income Funds** |  |
| MassMutual Core Bond Fund  | 16.2% |
| MassMutual Short-Duration Bond Fund  | 8.0% |
| Vanguard Total Bond Market Index Fund  | 6.5% |
| Vanguard Long-Term Treasury Index Fund  | 1.7% |
| MassMutual Total Return Bond Fund  | 22.6% |
| MassMutual Strategic Bond Fund  | 19.4% |
| **— Inflation Managed Funds** |  |
|  MassMutual Inflation-Protected and Income Fund  | 0.8% |
| **— High Yield Funds** |  |

---

---

| | |
|:---|:---|
| MassMutual High Yield Fund  | 0.3% |
| MassMutual Global Floating Rate Fund  | 0.1% |
| **— International Bond Funds** |  |
| Invesco International Bond Fund  | 4.0% |
| ***Other Funds***  | 0.5% |
| **— Commodities Funds** |  |
| &nbsp;&nbsp;&nbsp; DFA Commodity Strategy Fund  | 0.5% |

---

Note: Above allocations may not sum up to 100% due to rounding.

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying

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Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by

collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by

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changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers

or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income

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securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S.

currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

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***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies

will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market,

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economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject

to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith

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and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class R5 shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance and additional indexes, including an index that provides a comparison relevant to the Fund's allocation to equity investments (S&P 500<sup>®</sup> Index) and an index of funds with similar investment objectives (Lipper Balanced Fund Index). The Fund's name and investment strategy changed on February 1, 2020. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Average annual total returns for Class A shares of the Fund reflect any applicable sales charge. Performance for Class I, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) and performance for Class Y shares of the Fund for periods prior to its inception date (02/01/23) is based on the performance of Class R5 shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Class R5 Shares
![[MISSING IMAGE: j1m34131qk38dmmbn3e3277d092q.jpg]](j1m34131qk38dmmbn3e3277d092q.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20, | 8.41% | Lowest <br>Quarter: | 2Q '22, | –7.72% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class R5 only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
| | | **One<br>Year**  | **Five<br>Years**  | **Ten<br>Years** |
| Class R5  | Return Before <br> Taxes  | -13.51% | 1.80% | 3.11% |
| Class R5  | Return After Taxes on Distributions | -14.83% | 0.05% | 1.44% |
| Class R5  | Return After Taxes on Distributions and Sales of Fund Shares | -7.65% | 0.95% | 1.93% |
| Class I | Return Before <br> Taxes | -13.55% | 1.88% | 3.18% |
| Service Class | Return Before <br> Taxes | -13.75% | 1.69% | 3.00% |
| Administrative <br> Class | Return Before <br> Taxes | -13.78% | 1.60% | 2.91% |
| Class R4 | Return Before <br> Taxes | -13.92% | 1.41% | 2.74% |
| Class A | Return Before <br> Taxes | -18.66% | 0.20% | 2.07% |
| Class R3 | Return Before <br> Taxes | -14.08% | 1.19% | 2.49% |
| Class Y | Return Before <br> Taxes | -13.51% | 1.80% | 3.11% |
| Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | -13.01% | 0.02% | 1.06% |

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| | | | |
|:---|:---|:---|:---|
| | **One<br>Year**  | **Five<br>Years**  | **Ten<br>Years** |
| S&P 500 Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | -18.11% | 9.42% | 12.56% |
| Lipper Balanced Fund Index <br> (reflects no deduction for taxes) | -14.36% | 4.62% | 6.66% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (June 2011).

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available through distribution channels, such as broker-dealers or financial institutions, and to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

---

| | |
|:---|:---|
| **Purchase Minimums\*** | **Purchase Minimums\*** |
| | **Class Y**  |
| **Initial Investment** | **$100000**  |
| **Subsequent Investment** | **$250**  |

---

\*

The Fund reserves the right to change or waive the investment minimums. For retirement plans, the investment minimum is $250 for each of the initial investment and subsequent investments.

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual 40/60 Allocation Fund

#### INVESTMENT OBJECTIVE
The Fund seeks to achieve as high a total return over time as is considered consistent with prudent investment risk, preservation of capital and recognition of the Fund's stated asset allocation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |  |
| Other Expenses | 0.11%  | 0.21%  | 0.31%  | 0.41%  | 0.31%  | 0.41%  | 0.31%  | 0.21%<sup>(1)</sup>  |
|  Acquired Fund Fees and Expenses  | 0.44% | 0.44% | 0.44% | 0.44% | 0.44% | 0.44% | 0.44% | 0.44% |
|  **Total Annual Fund Operating Expenses<sup>(2)</sup>**  | **0.55%**  | **0.65%**  | **0.75%**  | **0.85%**  | **1.00%**  | **1.10%**  | **1.25%**  | **0.65%**  |
| Expense Reimbursement | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(3)</sup>  | 0.50% | 0.60% | 0.70% | 0.80% | 0.95% | 1.05% | 1.20% | 0.60% |

---

(1) Other Expenses are based on estimated amounts for the current fiscal year of the Fund.

(2) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(3) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.06%, 0.16%, 0.26%, 0.36%, 0.51%, 0.61%, 0.76%, and 0.16% for Classes I, R5, Service, Administrative, R4, A, R3, and Y, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $51 | $171 | $302 | $684 |
| Class R5 | $61 | $203 | $357 | $806 |
| Service Class | $72 | $235 | $412 | $926 |
|  Administrative Class  | $82 | $266 | $466 | $1044 |
| Class R4 | $97 | $313 | $548 | $1220 |
| Class A | $651 | $876 | $1118 | $1812 |
| Class R3 | $122 | $392 | $682 | $1507 |
| Class Y | $61 | $203 | $357 | $806 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 32% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers"). Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments.

The Fund typically invests approximately 40% of its assets in equity and similar funds and approximately 60% in fixed income funds, including money market funds. Under normal circumstances, the Fund's asset allocation between equity and fixed income funds is generally expected to vary by no more than plus or minus ten percentage points from this target asset allocation strategy. MML Advisers will generally attempt to select Underlying Funds that it expects will provide an aggregate exposure to "junk" or "high yield" bonds (securities rated below investment grade by Moody's or Standard & Poor's, or unrated securities determined to be of comparable quality by the applicable adviser or subadviser), including securities in default, of not more than 10% of the Fund's assets (although the Fund's exposure may from time to time exceed that percentage). The Fund is designed for use as part of an overall investment strategy by an investor who is saving for, or is already in, retirement.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers; the Fund will normally invest no more than 30% of its assets in mutual funds not advised by MML Advisers (referred to here as "non-affiliated" funds). Non-affiliated funds may include actively managed funds, or they may be passively managed funds seeking to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry. MML Advisers will select most of the Underlying Funds from among mutual funds advised by it even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers did not consider such factors or was not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, among various asset classes and Underlying Funds. MML Advisers does not intend to trade actively among

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Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers in its absolute discretion may modify the asset allocation strategy or the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| ***Equity Funds*** | 39.9% |
| **— U.S. Large Cap Equity Funds** |  |
| MassMutual Fundamental Value Fund  | 2.3% |
| MassMutual Diversified Value Fund  | 2.6% |
| MassMutual Equity Opportunities Fund  | 5.6% |
| MM Equity Asset Fund  | 10.3% |
| MassMutual Blue Chip Growth Fund | 3.8% |
| MassMutual Growth Opportunities Fund  | 1.0% |
| **— U.S. Small/Mid Cap Equity Funds** |  |
| MassMutual Mid Cap Value Fund  | 1.2% |
| Vanguard Mid-Cap Index Fund  | 1.6% |
| MassMutual Mid Cap Growth Fund  | 1.2% |
| MassMutual Small Cap Value Equity Fund | 0.6% |
| Vanguard Small-Cap Index Fund  | 0.6% |
| MassMutual Small Cap Growth Equity Fund  | 0.3% |
| **— REIT Funds** |  |
| Invesco Real Estate Fund  | 0.8% |
| **— International Equity Funds** |  |
| MassMutual Overseas Fund  | 2.7% |
| MassMutual International Equity Fund  | 1.4% |
| Vanguard Developed Markets Index Fund  | 2.7% |
| **— Emerging Markets Equity Funds** |  |
| MassMutual Strategic Emerging Markets Fund  | 0.6% |
| Vanguard Emerging Markets Stock Index Fund  | 0.6% |
| ***Fixed Income Funds***  | 59.6% |
| **— U.S. Fixed Income Funds** |  |
| MassMutual Core Bond Fund  | 12.1% |
| MassMutual Short-Duration Bond Fund  | 6.0% |
| Vanguard Total Bond Market Index Fund  | 4.8% |
| Vanguard Long-Term Treasury Index Fund  | 1.4% |
| MassMutual Total Return Bond Fund  | 16.9% |
| MassMutual Strategic Bond Fund  | 14.5% |
| **— Inflation Managed Funds** |  |
|  MassMutual Inflation-Protected and Income Fund  | 0.6% |
| **— High Yield Funds** |  |

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| | |
|:---|:---|
| MassMutual High Yield Fund  | 0.2% |
| MassMutual Global Floating Rate Fund  | 0.1% |
| **— International Bond Funds** |  |
| Invesco International Bond Fund  | 3.0% |
| ***Other Funds***  | 0.5% |
| **— Commodities Funds** |  |
| DFA Commodity Strategy Fund | 0.5% |

---

Note: Above allocations may not sum up to 100% due to rounding.

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying

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Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by

collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by

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changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers

or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income

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securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S.

currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

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***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies

will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market,

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economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject

to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith

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and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class R5 shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance and additional indexes, including an index that provides a comparison relevant to the Fund's allocation to fixed income investments (Bloomberg U.S. Aggregate Bond Index) and an index of funds with similar investment objectives (Lipper Balanced Fund Index). The Fund's name and investment strategy changed on February 1, 2020. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Average annual total returns for Class A shares of the Fund reflect any applicable sales charge. Performance for Class I, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) and performance for Class Y shares of the Fund for periods prior to its inception date (02/01/23) is based on the performance of Class R5 shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Class R5 Shares
![[MISSING IMAGE: ag05c1opgr4r668huqahqsh11a71.jpg]](ag05c1opgr4r668huqahqsh11a71.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20, | 11.57% | Lowest <br>Quarter: | 1Q '20, | –11.59% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class R5 only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Class R5  | Return Before <br> Taxes  | -14.39% | 3.29% | 5.21% |
| Class R5  | Return After Taxes on Distributions | -15.99% | 1.00% | 3.06% |
| Class R5  | Return After Taxes on Distributions and Sales of Fund Shares | -7.78% | 2.18% | 3.64% |
| Class I | Return Before <br> Taxes | -14.32% | 3.38% | 5.28% |
| Service Class | Return Before <br> Taxes | -14.48% | 3.17% | 5.11% |
| Administrative <br> Class | Return Before <br> Taxes | -14.59% | 3.07% | 5.00% |
| Class R4 | Return Before <br> Taxes | -14.72% | 2.92% | 4.83% |
| Class A | Return Before <br> Taxes | -19.42% | 1.67% | 4.16% |
| Class R3 | Return Before <br> Taxes | -14.89% | 2.65% | 4.57% |
| Class Y | Return Before <br> Taxes | -14.39% | 3.29% | 5.21% |
| S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | -18.11% | 9.42% | 12.56% |

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| | | | |
|:---|:---|:---|:---|
|  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | -13.01% | 0.02% | 1.06% |
| Lipper Balanced Fund Index <br> (reflects no deduction for taxes) | -14.36% | 4.62% | 6.66% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (June 2011).

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available through distribution channels, such as broker-dealers or financial institutions, and to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

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| | |
|:---|:---|
| **Purchase Minimums\*** | **Purchase Minimums\*** |
| | **Class Y**  |
| **Initial Investment** | **$100000**  |
| **Subsequent Investment** | **$250**  |

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\*

The Fund reserves the right to change or waive the investment minimums. For retirement plans, the investment minimum is $250 for each of the initial investment and subsequent investments.

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual 60/40 Allocation Fund

#### INVESTMENT OBJECTIVE
The Fund seeks to achieve as high a total return over time as is considered consistent with prudent investment risk, preservation of capital and recognition of the Fund's stated asset allocation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |  |
| Other Expenses | 0.11%  | 0.21%  | 0.31%  | 0.41%  | 0.31%  | 0.41%  | 0.31%  | 0.21%<sup>(1)</sup>  |
|  Acquired Fund Fees and Expenses  | 0.45%  | 0.45%  | 0.45%  | 0.45%  | 0.45%  | 0.45%  | 0.45%  | 0.45%  |
|  **Total Annual Fund Operating Expenses<sup>(2)</sup>**  | **0.56%**  | **0.66%**  | **0.76%**  | **0.86%**  | **1.01%**  | **1.11%**  | **1.26%**  | **0.66%**  |
| Expense Reimbursement | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  | (0.05%)  |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(3)</sup>  | 0.51%  | 0.61%  | 0.71%  | 0.81%  | 0.96%  | 1.06%  | 1.21%  | 0.61%  |

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(1) Other Expenses are based on estimated amounts for the current fiscal year of the Fund.

(2) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(3) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.06%, 0.16%, 0.26%, 0.36%, 0.51%, 0.61%, 0.76%, and 0.16% for Classes I, R5, Service, Administrative, R4, A, R3, and Y, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $52 | $174 | $308 | $697 |
| Class R5 | $62 | $206 | $363 | $818 |
| Service Class | $73 | $238 | $417 | $938 |
|  Administrative Class  | $83 | $269 | $472 | $1056 |
| Class R4 | $98 | $317 | $553 | $1232 |
| Class A | $652 | $879 | $1123 | $1823 |
| Class R3 | $123 | $395 | $687 | $1518 |
| Class Y | $62 | $206 | $363 | $818 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 26% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers"). Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments.

The Fund typically invests approximately 60% of its assets in equity and similar funds and approximately 40% in fixed income funds, including money market funds. Under normal circumstances, the Fund's asset allocation between equity and fixed income funds is generally expected to vary by no more than plus or minus ten percentage points from this target asset allocation strategy. MML Advisers will generally attempt to select Underlying Funds that it expects will provide an aggregate exposure to "junk" or "high yield" bonds (securities rated below investment grade by Moody's or Standard & Poor's, or unrated securities determined to be of comparable quality by the applicable adviser or subadviser), including securities in default, of not more than 10% of the Fund's assets (although the Fund's exposure may from time to time exceed that percentage). The Fund is designed for use as part of an overall investment strategy by an investor who is saving for, or is already in, retirement.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers; the Fund will normally invest no more than 30% of its assets in mutual funds not advised by MML Advisers (referred to here as "non-affiliated" funds). Non-affiliated funds may include actively managed funds, or they may be passively managed funds seeking to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry. MML Advisers will select most of the Underlying Funds from among mutual funds advised by it even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers did not consider such factors or was not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, among various asset classes and Underlying Funds. MML Advisers does not intend to trade actively among

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Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers in its absolute discretion may modify the asset allocation strategy or the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| ***Equity Funds*** | 60.1% |
| **— U.S. Large Cap Equity Funds** |  |
| MassMutual Fundamental Value Fund  | 3.7% |
| MassMutual Diversified Value Fund  | 4.1% |
| MassMutual Equity Opportunities Fund  | 9.1% |
| MM Equity Asset Fund  | 16.6% |
| MassMutual Blue Chip Growth Fund  | 6.2% |
| MassMutual Growth Opportunities Fund | 1.7% |
| **— U.S. Small/Mid Cap Equity Funds** |  |
| MassMutual Mid Cap Value Fund  | 1.8% |
| Vanguard Mid-Cap Index Fund  | 2.4% |
| MassMutual Mid Cap Growth Fund  | 1.8% |
| MassMutual Small Cap Value Equity Fund | 1.0% |
| Vanguard Small-Cap Index Fund  | 1.0% |
| MassMutual Small Cap Growth Equity Fund  | 0.5% |
| **— REIT Funds** |  |
| Invesco Real Estate Fund | 1.2% |
| **— International Equity Funds** |  |
| MassMutual Overseas Fund  | 3.1% |
| MassMutual International Equity Fund  | 1.6% |
| Vanguard Developed Markets Index Fund  | 3.1% |
| **— Emerging Markets Equity Funds** |  |
| MassMutual Strategic Emerging Markets Fund  | 0.6% |
| Vanguard Emerging Markets Stock Index Fund  | 0.6% |
| ***Fixed Income Funds***  | 39.6% |
| **— U.S. Fixed Income Funds** |  |
| MassMutual Core Bond Fund  | 7.9% |
| MassMutual Short-Duration Bond Fund  | 4.0% |
| Vanguard Total Bond Market Index Fund  | 3.2% |
| Vanguard Long-Term Treasury Index Fund  | 1.1% |
| MassMutual Total Return Bond Fund  | 11.2% |
| MassMutual Strategic Bond Fund  | 9.6% |
| **— Inflation Managed Funds** |  |
|  MassMutual Inflation-Protected and Income Fund  | 0.4% |
| **— High Yield Funds** |  |

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| | |
|:---|:---|
| MassMutual High Yield Fund  | 0.1% |
| MassMutual Global Floating Rate Fund  | 0.1% |
| **— International Bond Funds** |  |
| Invesco International Bond Fund  | 2.0% |
| ***Other Funds***  | 0.5% |
| **— Commodities Funds** |  |
| DFA Commodity Strategy Fund | 0.5% |

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Note: Above allocations may not sum up to 100% due to rounding.

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying

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Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by

collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by

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changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers

or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income

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securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S.

currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

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***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies

will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market,

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economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject

to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith

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and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class R5 shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance and additional indexes, including an index that provides a comparison relevant to the Fund's allocation to fixed income investments (Bloomberg U.S. Aggregate Bond Index) and an index of funds with similar investment objectives (Lipper Balanced Fund Index). The Fund's name and investment strategy changed on February 1, 2020. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Average annual total returns for Class A shares of the Fund reflect any applicable sales charge. Performance for Class I, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) and performance for Class Y shares of the Fund for periods prior to its inception date (02/01/23) is based on the performance of Class R5 shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Class R5 Shares
![[MISSING IMAGE: aeocki8nqgm26pk9r7fmat2jkbca.jpg]](aeocki8nqgm26pk9r7fmat2jkbca.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 14.65% | Lowest <br>Quarter: | 1Q '20,  | –15.92% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class R5 only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Class R5  | Return Before <br> Taxes  | -14.72% | 4.71% | 7.05% |
| Class R5  | Return After Taxes on Distributions | -17.03% | 1.78% | 4.44% |
| Class R5  | Return After Taxes on Distributions and Sales of Fund Shares | -7.35% | 3.27% | 5.11% |
| Class I | Return Before <br> Taxes | -14.62% | 4.82% | 7.12% |
| Service Class | Return Before <br> Taxes | -14.78% | 4.60% | 6.96% |
| Administrative <br> Class | Return Before <br> Taxes | -14.86% | 4.51% | 6.86% |
| Class R4 | Return Before <br> Taxes | -15.02% | 4.33% | 6.67% |
| Class A | Return Before <br> Taxes | -19.79% | 3.06% | 5.98% |
| Class R3 | Return Before <br> Taxes | -15.15% | 4.08% | 6.49% |
| Class Y | Return Before <br> Taxes | -14.72% | 4.71% | 7.05% |
| S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | -18.11% | 9.42% | 12.56% |

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| | | | |
|:---|:---|:---|:---|
|  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | -13.01% | 0.02% | 1.06% |
| Lipper Balanced Fund Index <br> (reflects no deduction for taxes) | -14.36% | 4.62% | 6.66% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (June 2011).

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available through distribution channels, such as broker-dealers or financial institutions, and to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

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| | |
|:---|:---|
| **Purchase Minimums\*** | **Purchase Minimums\*** |
| | **Class Y**  |
| **Initial Investment** | **$100000**  |
| **Subsequent Investment** | **$250**  |

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\*

The Fund reserves the right to change or waive the investment minimums. For retirement plans, the investment minimum is $250 for each of the initial investment and subsequent investments.

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual 80/20 Allocation Fund

#### INVESTMENT OBJECTIVE
The Fund seeks to achieve as high a total return over time as is considered consistent with prudent investment risk, preservation of capital and recognition of the Fund's stated asset allocation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  | **Class Y**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |  |
| Other Expenses | 0.15% | 0.25% | 0.35% | 0.45% | 0.35% | 0.45% | 0.35% | 0.25%<sup>(1)</sup> |
|  Acquired Fund Fees and Expenses  | 0.48% | 0.48% | 0.48% | 0.48% | 0.48% | 0.48% | 0.48% | 0.48% |
|  **Total Annual Fund Operating Expenses<sup>(2)</sup>**  | **0.63%**  | **0.73%**  | **0.83%**  | **0.93%**  | **1.08%**  | **1.18%**  | **1.33%**  | **0.73%**  |
| Expense Reimbursement | (0.06%) | (0.06%) | (0.06%) | (0.06%) | (0.06%) | (0.06%) | (0.06%) | (0.06%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(3)</sup>  | 0.57% | 0.67% | 0.77% | 0.87% | 1.02% | 1.12% | 1.27% | 0.67% |

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(1) Other Expenses are based on estimated amounts for the current fiscal year of the Fund.

(2) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(3) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.09%, 0.19%, 0.29%, 0.39%, 0.54%, 0.64%, 0.79%, and 0.19% for Classes I, R5, Service, Administrative, R4, A, R3, and Y, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $58 | $196 | $345 | $781 |
| Class R5 | $68 | $227 | $400 | $901 |
| Service Class | $79 | $259 | $455 | $1020 |
|  Administrative Class  | $89 | $290 | $509 | $1137 |
| Class R4 | $104 | $338 | $590 | $1312 |
| Class A | $658 | $898 | $1158 | $1898 |
| Class R3 | $129 | $415 | $723 | $1596 |
| Class Y | $68 | $227 | $400 | $901 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 28% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers"). Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments.

The Fund typically invests approximately 80% of its assets in equity and similar funds and approximately 20% in fixed income funds, including money market funds. Under normal circumstances, the Fund's asset allocation between equity and fixed income funds is generally expected to vary by no more than plus or minus ten percentage points from this target asset allocation strategy. The Fund is designed for use as part of an overall investment strategy by an investor who is saving for, or is already in, retirement.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers; the Fund will normally invest no more than 30% of its assets in mutual funds not advised by MML Advisers (referred to here as "non-affiliated" funds). Non-affiliated funds may include actively managed funds, or they may be passively managed funds seeking to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry. MML Advisers will select most of the Underlying Funds from among mutual funds advised by it even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers did not consider such factors or was not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, among various asset classes and Underlying Funds. MML Advisers does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers in its absolute discretion may modify the asset allocation strategy or the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to

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Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| ***Equity Funds*** | 80.0% |
| **— U.S. Large Cap Equity Funds** |  |
| MassMutual Fundamental Value Fund  | 4.6% |
| MassMutual Diversified Value Fund  | 5.1% |
| MassMutual Equity Opportunities Fund  | 11.3% |
| MM Equity Asset Fund  | 20.5% |
| MassMutual Blue Chip Growth Fund  | 7.7% |
| MassMutual Growth Opportunities Fund  | 2.1% |
| **— U.S. Small/Mid Cap Equity Funds** |  |
| MassMutual Mid Cap Value Fund  | 2.4% |
| Vanguard Mid-Cap Index Fund  | 3.2% |
| MassMutual Mid Cap Growth Fund  | 2.4% |
| MassMutual Small Cap Value Equity Fund | 1.3% |
| Vanguard Small-Cap Index Fund  | 1.3% |
| MassMutual Small Cap Growth Equity Fund  | 0.6% |
| **— REIT Funds** |  |
| Invesco Real Estate Fund  | 1.6% |
| **— International Equity Funds** |  |
| MassMutual Overseas Fund  | 5.4% |
| MassMutual International Equity Fund  | 2.7% |
| Vanguard Developed Markets Index Fund  | 5.4% |
| **— Emerging Markets Equity Funds** |  |
| MassMutual Strategic Emerging Markets Fund  | 1.2% |
| Vanguard Emerging Markets Stock Index Fund  | 1.2% |
| ***Fixed Income Funds***  | 19.7% |
| **— U.S. Fixed Income Funds** |  |
| MassMutual Core Bond Fund  | 3.9% |
| MassMutual Short-Duration Bond Fund | 2.0% |
| Vanguard Total Bond Market Index Fund  | 1.6% |
| Vanguard Long-Term Treasury Index Fund  | 0.8% |
| MassMutual Total Return Bond Fund | 5.4% |
| MassMutual Strategic Bond Fund  | 4.6% |
| **— Inflation Managed Funds** |  |
|  MassMutual Inflation-Protected and Income Fund  | 0.2% |
| **— High Yield Funds** |  |
| MassMutual High Yield Fund | 0.1% |
| MassMutual Global Floating Rate Fund  | 0.1% |
| **— International Bond Funds** |  |
| Invesco International Bond Fund  | 1.0% |
| ***Other Funds*** | 0.5% |
| **— Commodities Funds** |  |
| DFA Commodity Strategy Fund | 0.5% |

---

Note: Above allocations may not sum up to 100% due to rounding.

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

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#### Principal Risks
The following are the Principal Risks of the Fund. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its

obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it

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difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of

imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk

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that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S.

companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

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***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are

subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest

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rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk

to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not

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recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class R5 shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance and additional indexes, including an index that provides a comparison relevant to the Fund's allocation to fixed income investments (Bloomberg U.S. Aggregate Bond Index) and an index of funds with similar investment objectives (Lipper Balanced Fund Index). The Fund's name and investment strategy changed on February 1, 2020. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Average annual total returns for Class A shares of the Fund reflect any applicable sales charge. Performance for Class I, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) and performance for Class Y shares of the Fund for periods prior to its inception date (02/01/23) is based on the performance of Class R5 shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Class R5 Shares
![[MISSING IMAGE: b2e8754vqc94dmscggaij780dmaa.jpg]](b2e8754vqc94dmscggaij780dmaa.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 16.93% | Lowest <br>Quarter: | 1Q '20,  | –18.76% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class R5 only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Class R5  | Return Before <br> Taxes  | -15.58% | 5.38% | 7.94% |
| Class R5  | Return After Taxes on Distributions | -18.18% | 2.45% | 5.45% |
| Class R5  | Return After Taxes on Distributions and Sales of Fund Shares | -7.54% | 3.87% | 5.96% |
| Class I | Return Before <br> Taxes | -15.60% | 5.45% | 7.99% |
| Service Class | Return Before <br> Taxes | -15.77% | 5.25% | 7.82% |
| Administrative <br> Class | Return Before <br> Taxes | -15.79% | 5.15% | 7.71% |
| Class R4 | Return Before <br> Taxes | -15.99% | 4.98% | 7.53% |

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years** |
| Class A | Return Before <br> Taxes | -20.63% | 3.71% | 6.85% |
| Class R3 | Return Before <br> Taxes | -16.15% | 4.73% | 7.27% |
| Class Y | Return Before <br> Taxes | -15.58% | 5.38% | 7.94% |
| S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | S&P 500<sup>®</sup> Index (reflects no <br> deduction for fees, expenses, or <br> taxes) | -18.11% | 9.42% | 12.56% |
| Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | Bloomberg U.S. Aggregate Bond <br> Index (reflects no deduction for <br> fees, expenses, or taxes) | -13.01% | 0.02% | 1.06% |
| Lipper Balanced Fund Index <br> (reflects no deduction for taxes) | Lipper Balanced Fund Index <br> (reflects no deduction for taxes) | -14.36% | 4.62% | 6.66% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (June 2011).

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available through distribution channels, such as broker-dealers or financial institutions, and to retirement plans, other institutional investors, and individual retirement

accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

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| | |
|:---|:---|
| **Purchase Minimums\*** | **Purchase Minimums\*** |
| | **Class Y**  |
| **Initial Investment** | **$100000**  |
| **Subsequent Investment** | **$250**  |

---

\*

The Fund reserves the right to change or waive the investment minimums. For retirement plans, the investment minimum is $250 for each of the initial investment and subsequent investments.

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan In Retirement Fund

#### INVESTMENT OBJECTIVE
The Fund seeks current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.22% | 0.32% | 0.42% | 0.52% | 0.42% | 0.52% | 0.42% |
|  Acquired Fund Fees and Expenses  | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.65%**  | **0.75%**  | **0.85%**  | **0.95%**  | **1.10%**  | **1.20%**  | **1.35%**  |
| Expense Reimbursement | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.49% | 0.59% | 0.69% | 0.79% | 0.94% | 1.04% | 1.19% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.06%, 0.16%, 0.26%, 0.36%, 0.51%, 0.61%, and 0.76% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund

for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that

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the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $50 | $192 | $346 | $795 |
| Class R5 | $60 | $224 | $401 | $915 |
| Service Class | $70 | $255 | $456 | $1034 |
|  Administrative Class  | $81 | $287 | $510 | $1152 |
| Class R4 | $96 | $334 | $591 | $1326 |
| Class A | $650 | $895 | $1159 | $1911 |
| Class R3 | $121 | $412 | $724 | $1610 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 58% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who are retired or expect to retire soon. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation and tactical asset allocation (adjusting the Fund's specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market

instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's assets are allocated among Underlying Funds according to an asset allocation strategy that emphasizes fixed income and money market funds, but also includes smaller allocations to equity and certain other funds.

The table below shows the Fund's strategic target allocations among asset and sub-asset classes as of February 1, 2023.

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Fixed Income** | **55.00%** |
| U.S. Fixed Income | 36.50% |
| Inflation Managed | 7.50% |
| High Yield Fixed Income  | 9.35% |
| Emerging Markets Debt  | 1.65% |
| **Equity** | **40.00%** |
| U.S. Large Cap Equity | 19.60% |
| U.S. Mid Cap Equity | 2.80% |
| U.S. Small Cap Equity  | 2.40% |
| REITs  | 0.80% |
| International Equity  | 11.20% |
| Emerging Markets Equity  | 3.20% |
| **Money Market/Cash and Cash Equivalents** | **5.00%** |
| Money Market/Cash and Cash Equivalents | 5.00% |

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(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various

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factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund | 9.06% |
| MassMutual Core Bond Fund | 20.42% |
| Vanguard Total Bond Market Index Fund | 5.14% |
| MassMutual Total Return Bond Fund | 6.89% |
| MassMutual Strategic Bond Fund | 6.92% |
|  MassMutual Inflation-Protected and Income Fund  | 7.39% |
| MassMutual High Yield Fund  | 5.28% |
|  JPMorgan U.S. Government Money Market Fund | 12.60% |

---

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies

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in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of

Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments listed above. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed above from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of

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redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing

demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its

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ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at

unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S.

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company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of

countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

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***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such

as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly

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the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading,

operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, and Class R4 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 shares to reflect Class R4 expenses. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

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#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: ahkptcr00v9cqcq2vql3j7tngjc6.jpg]](ahkptcr00v9cqcq2vql3j7tngjc6.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 9.93% | Lowest <br>Quarter: | 1Q '20,  | –10.58% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -14.29% | 2.12% | 3.32% |
| Service Class  | Return After Taxes on Distributions | -16.34% | 0.07% | 1.81% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.00% | 1.22% | 2.17% |
| Class I | Return Before <br> Taxes | -14.16% | 2.33% | 3.83% |
| Class R5 | Return Before <br> Taxes | -14.20% | 2.23% | 3.48% |
| Administrative <br> Class | Return Before <br> Taxes | -14.43% | 2.02% | 3.22% |
| Class R4 | Return Before <br> Taxes | -14.50% | 1.86% | 3.04% |
| Class A | Return Before <br> Taxes | -19.30% | 0.62% | 2.37% |
| Class R3 | Return Before <br> Taxes | -14.76% | 1.62% | 2.78% |
| S&P Target Date Retirement <br> Income Index (reflects no deduction <br> for fees, expenses, or taxes) | S&P Target Date Retirement <br> Income Index (reflects no deduction <br> for fees, expenses, or taxes) | -11.17% | 2.33% | 3.59% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since December 2006.

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2020 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

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| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.11% | 0.21% | 0.31% | 0.41% | 0.31% | 0.41% | 0.31% |
|  Acquired Fund Fees and Expenses  | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% | 0.43% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.54%**  | **0.64%**  | **0.74%**  | **0.84%**  | **0.99%**  | **1.09%**  | **1.24%**  |
| Expense Reimbursement | (0.07%) | (0.07%) | (0.07%) | (0.07%) | (0.07%) | (0.07%) | (0.07%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.47% | 0.57% | 0.67% | 0.77% | 0.92% | 1.02% | 1.17% |

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(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.04%, 0.14%, 0.24%, 0.34%, 0.49%, 0.59%, and 0.74% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $48 | $166 | $295 | $670 |
| Class R5 | $58 | $198 | $350 | $792 |
| Service Class | $68 | $230 | $405 | $912 |
|  Administrative Class  | $79 | $261 | $459 | $1031 |
| Class R4 | $94 | $308 | $540 | $1207 |
| Class A | $648 | $871 | $1111 | $1800 |
| Class R3 | $119 | $387 | $674 | $1494 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 52% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who retired on or around the year 2020 (the target retirement year) and plan to withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2055, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, which the Fund has now reached, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is in the Spending Phase, its portfolio reflects a greater emphasis on fixed income investments and less emphasis on equity investments than a similar fund whose Spending Phase will begin later.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: it7747t2bk57iqfo9iambug9mcbe.jpg]](it7747t2bk57iqfo9iambug9mcbe.jpg)

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| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Fixed Income** | **55.00%** |
| U.S. Fixed Income | 36.50% |
| Inflation Managed | 7.50% |
| High Yield Fixed Income  | 9.35% |
| Emerging Markets Debt  | 1.65% |
| **Equity** | **40.00%** |
| U.S. Large Cap Equity | 19.60% |
| U.S. Mid Cap Equity | 2.80% |
| U.S. Small Cap Equity  | 2.40% |
| REITs  | 0.80% |
| International Equity  | 11.20% |
| Emerging Markets Equity  | 3.20% |
| **Money Market/Cash and Cash Equivalents** | **5.00%** |
| Money Market/Cash and Cash Equivalents | 5.00% |

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(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2055. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund | 9.05% |
| MassMutual Core Bond Fund | 20.42% |
| Vanguard Total Bond Market Index Fund | 5.14% |
| MassMutual Total Return Bond Fund | 6.89% |
| MassMutual Strategic Bond Fund  | 6.92% |
|  MassMutual Inflation-Protected and Income Fund | 7.39% |
| MassMutual High Yield Fund | 5.28% |
|  JPMorgan U.S. Government Money Market Fund | 12.60% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to

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gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded

funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers,

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such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments

and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create

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investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at

a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than

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securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market

fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's

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performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by

J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

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***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any

other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

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***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, and Class R4 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 shares to reflect Class R4 expenses. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: ansjfqk62eaipuvrr6v5f5momvsn.jpg]](ansjfqk62eaipuvrr6v5f5momvsn.jpg)

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 10.27% | Lowest <br>Quarter: | 1Q '20,  | –11.16% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

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#### Average Annual Total Returns
(for the periods ended December 31, 2022)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -14.36% | 2.48% | 4.99% |
| Service Class  | Return After Taxes on Distributions | -15.70% | 0.27% | 3.34% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.02% | 1.52% | 3.56% |
| Class I | Return Before <br> Taxes | -14.13% | 2.69% | 5.18% |
| Class R5 | Return Before <br> Taxes | -14.17% | 2.60% | 5.09% |
| Administrative <br> Class | Return Before <br> Taxes | -14.38% | 2.40% | 4.90% |
| Class R4 | Return Before <br> Taxes | -14.51% | 2.24% | 4.73% |
| Class A | Return Before <br> Taxes | -19.29% | 0.97% | 4.03% |
| Class R3 | Return Before <br> Taxes | -14.71% | 1.99% | 4.45% |
| S&P Target Date 2020 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2020 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -12.81% | 3.14% | 5.50% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio

manager at MML Advisers. He has managed the Fund since December 2006.

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2025 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.13% | 0.23% | 0.33% | 0.43% | 0.33% | 0.43% | 0.33% |
|  Acquired Fund Fees and Expenses  | 0.46% | 0.46% | 0.46% | 0.46% | 0.46% | 0.46% | 0.46% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.59%**  | **0.69%**  | **0.79%**  | **0.89%**  | **1.04%**  | **1.14%**  | **1.29%**  |
| Expense Reimbursement | (0.12%) | (0.12%) | (0.12%) | (0.12%) | (0.12%) | (0.12%) | (0.12%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.47% | 0.57% | 0.67% | 0.77% | 0.92% | 1.02% | 1.17% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.01%, 0.11%, 0.21%, 0.31%, 0.46%, 0.56%, and 0.71% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $48 | $177 | $317 | $726 |
| Class R5 | $58 | $209 | $372 | $847 |
| Service Class | $68 | $240 | $427 | $967 |
|  Administrative Class  | $79 | $272 | $481 | $1085 |
| Class R4 | $94 | $319 | $562 | $1260 |
| Class A | $648 | $881 | $1132 | $1850 |
| Class R3 | $119 | $397 | $696 | $1546 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 54% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2025 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2060, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is only a few years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on fixed income investments and less emphasis on equity investments than a similar fund whose Spending Phase will begin later.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: p3smmb0h0pvl4d8oihv4dkifpfau.jpg]](p3smmb0h0pvl4d8oihv4dkifpfau.jpg)

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity**  | 53.00% |
| U.S. Large Cap Equity  | 25.97% |
| U.S. Mid Cap Equity | 3.71% |
| U.S. Small Cap Equity  | 3.18% |
| REITs  | 1.06% |
| International Equity  | 14.31% |
| Emerging Markets Equity  | 4.77% |
| **Fixed Income**  | 47.00% |
| U.S. Fixed Income | 34.60% |
| Inflation Managed  | 3.00% |
| High Yield Fixed Income  | 8.00% |
| Emerging Markets Debt  | 1.40% |
| **Money Market/Cash and Cash Equivalents**  | 0.00% |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2060. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund  | 11.70% |
| Vanguard Developed Markets Index Fund | 5.20% |
| MassMutual Core Bond Fund  | 19.05% |
| MassMutual Total Return Bond Fund  | 6.43% |
| MassMutual Strategic Bond Fund  | 6.46% |
| MassMutual High Yield Fund | 5.14% |
|  JPMorgan U.S. Government Money Market Fund | 7.54% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: ufh7ag2e1sh92adrei25pu765lbu.jpg]](ufh7ag2e1sh92adrei25pu765lbu.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 12.48% | Lowest <br>Quarter: | 1Q '20, | –14.03% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through

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tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -15.28% | 3.27% | 5.90% |
| Service Class  | Return After Taxes on Distributions | -17.20% | 0.71% | 3.86% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.11% | 2.17% | 4.28% |
| Class I | Return Before <br> Taxes | -15.20% | 3.47% | 6.07% |
| Class R5 | Return Before <br> Taxes | -15.27% | 3.39% | 6.00% |
| Administrative <br> Class | Return Before <br> Taxes | -15.42% | 3.17% | 5.80% |
| Class R4 | Return Before <br> Taxes | -15.57% | 3.01% | 5.62% |
| Class A | Return Before <br> Taxes | -20.26% | 1.76% | 4.93% |
| Class R3 | Return Before <br> Taxes | -15.74% | 2.77% | 5.38% |
| S&P Target Date 2025 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2025 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -13.13% | 3.75% | 6.23% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (April 2010).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2030 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.07% | 0.17% | 0.27% | 0.37% | 0.27% | 0.37% | 0.27% |
|  Acquired Fund Fees and Expenses  | 0.47% | 0.47% | 0.47% | 0.47% | 0.47% | 0.47% | 0.47% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.54%**  | **0.64%**  | **0.74%**  | **0.84%**  | **0.99%**  | **1.09%**  | **1.24%**  |
| Expense Reimbursement | (0.03%) | (0.03%) | (0.03%) | (0.03%) | (0.03%) | (0.03%) | (0.03%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.51% | 0.61% | 0.71% | 0.81% | 0.96% | 1.06% | 1.21% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.04%, 0.14%, 0.24%, 0.34%, 0.49%, 0.59%, and 0.74% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $52 | $170 | $299 | $674 |
| Class R5 | $62 | $202 | $354 | $796 |
| Service Class | $73 | $234 | $409 | $916 |
|  Administrative Class  | $83 | $265 | $463 | $1034 |
| Class R4 | $98 | $312 | $544 | $1210 |
| Class A | $652 | $875 | $1115 | $1803 |
| Class R3 | $123 | $390 | $678 | $1497 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 58% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2030 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2065, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: adat1392s8se3k7kttkfuhgf5okq.jpg]](adat1392s8se3k7kttkfuhgf5okq.jpg)

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| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity**  | 66.00% |
| U.S. Large Cap Equity  | 32.34% |
| U.S. Mid Cap Equity | 4.62% |
| U.S. Small Cap Equity  | 3.96% |
| REITs  | 1.32% |
| International Equity  | 17.82% |
| Emerging Markets Equity  | 5.94% |
| **Fixed Income**  | 34.00% |
| U.S. Fixed Income | 27.20% |
| Inflation Managed  | 0.00% |
| High Yield Fixed Income  | 5.78% |
| Emerging Markets Debt  | 1.03% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2065. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund | 14.83% |
| MassMutual Overseas Fund | 5.22% |
| Vanguard Developed Markets Index Fund | 6.63% |
| MassMutual Core Bond Fund | 15.24% |
| MassMutual Total Return Bond Fund | 5.14% |
| MassMutual Strategic Bond Fund | 5.17% |
|  JPMorgan U.S. Government Money Market Fund | 5.96% |

---

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, and Class R4 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 shares to reflect Class R4 expenses. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: acn7ssprhmm2v8llr2c58mrogg2p.jpg]](acn7ssprhmm2v8llr2c58mrogg2p.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 13.89% | Lowest <br>Quarter: | 1Q '20,  | –16.42% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

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#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -15.83% | 3.80% | 6.44% |
| Service Class  | Return After Taxes on Distributions | -17.91% | 1.18% | 4.50% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.22% | 2.63% | 4.81% |
| Class I | Return Before <br> Taxes | -15.74% | 4.00% | 6.62% |
| Class R5 | Return Before <br> Taxes | -15.74% | 3.90% | 6.52% |
| Administrative <br> Class | Return Before <br> Taxes | -15.93% | 3.69% | 6.34% |
| Class R4 | Return Before <br> Taxes | -16.03% | 3.53% | 6.16% |
| Class A | Return Before <br> Taxes | -20.76% | 2.27% | 5.46% |
| Class R3 | Return Before <br> Taxes | -16.21% | 3.29% | 5.89% |
| S&P Target Date 2030 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2030 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -13.96% | 4.17% | 6.84% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio

manager at MML Advisers. He has managed the Fund since December 2006.

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2035 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

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**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.13% | 0.23% | 0.33% | 0.43% | 0.33% | 0.43% | 0.33% |
|  Acquired Fund Fees and Expenses  | 0.49% | 0.49% | 0.49% | 0.49% | 0.49% | 0.49% | 0.49% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.62%**  | **0.72%**  | **0.82%**  | **0.92%**  | **1.07%**  | **1.17%**  | **1.32%**  |
| Expense Reimbursement | (0.08%) | (0.08%) | (0.08%) | (0.08%) | (0.08%) | (0.08%) | (0.08%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.54% | 0.64% | 0.74% | 0.84% | 0.99% | 1.09% | 1.24% |

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(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.05%, 0.15%, 0.25%, 0.35%, 0.50%, 0.60%, and 0.75% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $55 | $190 | $338 | $767 |
| Class R5 | $65 | $222 | $393 | $887 |
| Service Class | $76 | $254 | $447 | $1006 |
|  Administrative Class  | $86 | $285 | $501 | $1124 |
| Class R4 | $101 | $332 | $582 | $1298 |
| Class A | $655 | $894 | $1151 | $1886 |
| Class R3 | $126 | $410 | $716 | $1583 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 63% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2035 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2070, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: l4pus3o6459qn1oujh41mn2qbj5t.jpg]](l4pus3o6459qn1oujh41mn2qbj5t.jpg)

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| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity** | **78.00%** |
| U.S. Large Cap Equity  | 38.22% |
| U.S. Mid Cap Equity | 5.46% |
| U.S. Small Cap Equity  | 4.68% |
| REITs  | 1.56% |
| International Equity  | 21.06% |
| Emerging Markets Equity  | 7.02% |
| **Fixed Income**  | 22.00% |
| U.S. Fixed Income | 17.60% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income  | 3.75% |
| Emerging Markets Debt  | 0.65% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

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(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2070. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund  | 17.76% |
| MassMutual Blue Chip Growth Fund | 5.41% |
| MassMutual Overseas Fund | 7.21% |
| Vanguard Developed Markets Index Fund | 6.18% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 5.18% |
| MassMutual Total Return Bond Fund | 7.40% |
| MassMutual Strategic Bond Fund | 7.43% |
|  JPMorgan U.S. Government Money Market Fund | 5.21% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to

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gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded

funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers,

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such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments

and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create

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investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at

a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than

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securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market

fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's

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performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by

J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

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***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any

other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

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***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: iacvmcal0fpok41g0dpafbcb9ph0.jpg]](iacvmcal0fpok41g0dpafbcb9ph0.jpg)

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 15.70% | Lowest <br>Quarter: | 1Q '20,  | –18.90% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through

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tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -16.73% | 4.17% | 6.83% |
| Service Class  | Return After Taxes on Distributions | -18.96% | 1.43% | 4.76% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.50% | 2.98% | 5.16% |
| Class I | Return Before <br> Taxes | -16.55% | 4.38% | 7.01% |
| Class R5 | Return Before <br> Taxes | -16.65% | 4.28% | 6.92% |
| Administrative <br> Class | Return Before <br> Taxes | -16.79% | 4.07% | 6.73% |
| Class R4 | Return Before <br> Taxes | -16.98% | 3.90% | 6.56% |
| Class A | Return Before <br> Taxes | -21.60% | 2.64% | 5.84% |
| Class R3 | Return Before <br> Taxes | -17.13% | 3.66% | 6.30% |
| S&P Target Date 2035 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2035 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -14.99% | 4.63% | 7.42% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (April 2010).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2040 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.09% | 0.19% | 0.29% | 0.39% | 0.29% | 0.39% | 0.29% |
|  Acquired Fund Fees and Expenses  | 0.50% | 0.50% | 0.50% | 0.50% | 0.50% | 0.50% | 0.50% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.59%**  | **0.69%**  | **0.79%**  | **0.89%**  | **1.04%**  | **1.14%**  | **1.29%**  |
| Expense Reimbursement | (0.05%) | (0.05%) | (0.05%) | (0.05%) | (0.05%) | (0.05%) | (0.05%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.54% | 0.64% | 0.74% | 0.84% | 0.99% | 1.09% | 1.24% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.04%, 0.14%, 0.24%, 0.34%, 0.49%, 0.59%, and 0.74% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $55 | $184 | $324 | $733 |
| Class R5 | $65 | $216 | $379 | $854 |
| Service Class | $76 | $247 | $434 | $973 |
|  Administrative Class  | $86 | $279 | $488 | $1091 |
| Class R4 | $101 | $326 | $569 | $1266 |
| Class A | $655 | $888 | $1139 | $1856 |
| Class R3 | $126 | $404 | $703 | $1552 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 61% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2040 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2075, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: kvlbrlk5p8n4r9d4d11lrlegq5jf.jpg]](kvlbrlk5p8n4r9d4d11lrlegq5jf.jpg)

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity**  | 87.00% |
| U.S. Large Cap Equity  | 42.63% |
| U.S. Mid Cap Equity | 6.09% |
| U.S. Small Cap Equity  | 5.22% |
| REITs  | 1.74% |
| International Equity  | 23.06% |
| Emerging Markets Equity  | 8.27% |
| **Fixed Income**  | 13.00% |
| U.S. Fixed Income | 10.40% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income  | 2.20% |
| Emerging Markets Debt  | 0.40% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2075. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MM Equity Asset Fund  | 20.08% |
| MassMutual Blue Chip Growth Fund | 6.11% |
| MassMutual Overseas Fund | 8.37% |
| MassMutual International Equity Fund | 5.06% |
| Vanguard Developed Markets Index Fund | 7.17% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 5.74% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the

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duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, and Class R4 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 shares to reflect Class R4 expenses. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: nulogbinko49df6h6asn3ls2p0lr.jpg]](nulogbinko49df6h6asn3ls2p0lr.jpg)

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 16.93% | Lowest <br>Quarter: | 1Q '20,  | –20.87% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

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#### Average Annual Total Returns
(for the periods ended December 31, 2022)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -16.90% | 4.57% | 7.10% |
| Service Class  | Return After Taxes on Distributions | -19.16% | 1.91% | 5.06% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.52% | 3.31% | 5.39% |
| Class I | Return Before <br> Taxes | -16.70% | 4.79% | 7.26% |
| Class R5 | Return Before <br> Taxes | -16.79% | 4.69% | 7.20% |
| Administrative <br> Class | Return Before <br> Taxes | -16.98% | 4.47% | 6.99% |
| Class R4 | Return Before <br> Taxes | -17.12% | 4.33% | 6.84% |
| Class A | Return Before <br> Taxes | -21.79% | 3.02% | 6.10% |
| Class R3 | Return Before <br> Taxes | -17.37% | 4.04% | 6.52% |
| S&P Target Date 2040 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2040 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -15.56% | 4.97% | 7.84% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio

manager at MML Advisers. He has managed the Fund since December 2006.

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2045 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.18% | 0.28% | 0.38% | 0.48% | 0.38% | 0.48% | 0.38% |
|  Acquired Fund Fees and Expenses  | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.69%**  | **0.79%**  | **0.89%**  | **0.99%**  | **1.14%**  | **1.24%**  | **1.39%**  |
| Expense Reimbursement | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) | (0.16%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.53% | 0.63% | 0.73% | 0.83% | 0.98% | 1.08% | 1.23% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.02%, 0.12%, 0.22%, 0.32%, 0.47%, 0.57%, and 0.72% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $54 | $205 | $368 | $843 |
| Class R5 | $64 | $236 | $423 | $963 |
| Service Class | $75 | $268 | $477 | $1081 |
|  Administrative Class  | $85 | $299 | $532 | $1198 |
| Class R4 | $100 | $346 | $612 | $1372 |
| Class A | $654 | $907 | $1179 | $1954 |
| Class R3 | $125 | $424 | $745 | $1655 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 63% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2045 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2080, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: q0fo01mprdno8f0qhkpmmqe39kfc.jpg]](q0fo01mprdno8f0qhkpmmqe39kfc.jpg)

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity**  | 94.00% |
| U.S. Large Cap Equity  | 46.06% |
| U.S. Mid Cap Equity | 6.58% |
| U.S. Small Cap Equity  | 5.64% |
| REITs  | 1.88% |
| International Equity  | 24.91% |
| Emerging Markets Equity  | 8.93% |
| **Fixed Income**  | 6.00% |
| U.S. Fixed Income | 4.80% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income  | 0.85% |
| Emerging Markets Debt  | 0.35% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2080. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MassMutual Equity Opportunities Fund | 5.93% |
| MM Equity Asset Fund | 20.19% |
| MassMutual Blue Chip Growth Fund | 6.65% |
| MassMutual Overseas Fund | 9.13% |
| MassMutual International Equity Fund | 5.50% |
| Vanguard Developed Markets Index Fund | 7.83% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 6.29% |

---

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: kh961u0mbf6csha1v0aforkrou37.jpg]](kh961u0mbf6csha1v0aforkrou37.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 17.94% | Lowest <br>Quarter: | 1Q '20,  | –22.27% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through

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tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -17.19% | 4.96% | 7.52% |
| Service Class  | Return After Taxes on Distributions | -19.86% | 1.95% | 5.30% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.34% | 3.65% | 5.77% |
| Class I | Return Before <br> Taxes | -16.97% | 5.19% | 7.71% |
| Class R5 | Return Before <br> Taxes | -17.10% | 5.06% | 7.62% |
| Administrative <br> Class | Return Before <br> Taxes | -17.17% | 4.88% | 7.43% |
| Class R4 | Return Before <br> Taxes | -17.34% | 4.72% | 7.27% |
| Class A | Return Before <br> Taxes | -21.99% | 3.44% | 6.54% |
| Class R3 | Return Before <br> Taxes | -17.63% | 4.44% | 6.99% |
| S&P Target Date 2045 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2045 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -15.84% | 5.16% | 8.11% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (April 2010).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2050 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.12%  | 0.22%  | 0.32%  | 0.42%  | 0.32%  | 0.42%  | 0.32%  |
|  Acquired Fund Fees and Expenses  | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.63%**  | **0.73%**  | **0.83%**  | **0.93%**  | **1.08%**  | **1.18%**  | **1.33%**  |
| Expense Reimbursement | (0.10%)  | (0.10%)  | (0.10%)  | (0.10%)  | (0.10%)  | (0.10%)  | (0.10%)  |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.53% | 0.63% | 0.73% | 0.83% | 0.98% | 1.08% | 1.23% |

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(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.02%, 0.12%, 0.22%, 0.32%, 0.47%, 0.57%, and 0.72% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $54 | $191 | $341 | $777 |
| Class R5 | $64 | $223 | $396 | $897 |
| Service Class | $74 | $255 | $450 | $1016 |
|  Administrative Class  | $84 | $286 | $505 | $1134 |
| Class R4 | $100 | $333 | $585 | $1308 |
| Class A | $654 | $894 | $1154 | $1894 |
| Class R3 | $125 | $411 | $719 | $1592 |

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#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 60% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2050 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2085, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: anl1i4j2fi2t7sosuv7glpba0e99.jpg]](anl1i4j2fi2t7sosuv7glpba0e99.jpg)

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| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity** | **94.00%** |
| U.S. Large Cap Equity  | 46.06% |
| U.S. Mid Cap Equity | 6.58% |
| U.S. Small Cap Equity  | 5.64% |
| REITs  | 1.88% |
| International Equity  | 24.91% |
| Emerging Markets Equity  | 8.93% |
| **Fixed Income** | **6.00%** |
| U.S. Fixed Income | 4.80% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income | 0.85% |
| Emerging Markets Debt | 0.35% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

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(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2085. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MassMutual Equity Opportunities Fund | 6.06% |
| MM Equity Asset Fund  | 20.46% |
| MassMutual Blue Chip Growth Fund | 6.76% |
| MassMutual Overseas Fund | 9.26% |
| MassMutual International Equity Fund | 5.60% |
| Vanguard Developed Markets Index Fund | 7.92% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 6.41% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, and Class R4 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 shares to reflect Class R4 expenses. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: gqh4viuekn864oulqb3cdql8q47f.jpg]](gqh4viuekn864oulqb3cdql8q47f.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 17.92% | Lowest <br>Quarter: | 1Q '20,  | –22.34% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

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#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years**  | **Ten <br>Years**  |
| Service Class  | Return Before <br> Taxes  | -17.15% | 5.04% | 7.66% |
| Service Class  | Return After Taxes on Distributions | -19.42% | 2.29% | 5.31% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.61% | 3.66% | 5.77% |
| Class I | Return Before <br> Taxes | -16.98% | 5.21% | 7.83% |
| Class R5 | Return Before <br> Taxes | -17.09% | 5.12% | 7.75% |
| Administrative <br> Class | Return Before <br> Taxes | -17.23% | 4.91% | 7.56% |
| Class R4 | Return Before <br> Taxes | -17.38% | 4.76% | 7.39% |
| Class A | Return Before <br> Taxes | -21.97% | 3.50% | 6.68% |
| Class R3 | Return Before <br> Taxes | -17.66% | 4.48% | 7.09% |
| S&P Target Date 2050 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2050 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -15.97% | 5.26% | 8.33% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio

manager at MML Advisers. He has managed the Fund since its inception (December 2007).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2055 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.34% | 0.44% | 0.54% | 0.64% | 0.54% | 0.64% | 0.54% |
|  Acquired Fund Fees and Expenses  | 0.52% | 0.52% | 0.52% | 0.52% | 0.52% | 0.52% | 0.52% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **0.86%**  | **0.96%**  | **1.06%**  | **1.16%**  | **1.31%**  | **1.41%**  | **1.56%**  |
| Expense Reimbursement | (0.34%) | (0.34%) | (0.34%) | (0.34%) | (0.34%) | (0.34%) | (0.34%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.52% | 0.62% | 0.72% | 0.82% | 0.97% | 1.07% | 1.22% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.00%, 0.10%, 0.20%, 0.30%, 0.45%, 0.55%, and 0.70% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $53 | $240 | $443 | $1029 |
| Class R5 | $63 | $272 | $498 | $1147 |
| Service Class | $74 | $303 | $552 | $1263 |
|  Administrative Class  | $84 | $335 | $606 | $1379 |
| Class R4 | $99 | $382 | $686 | $1549 |
| Class A | $653 | $940 | $1248 | $2120 |
| Class R3 | $124 | $459 | $818 | $1828 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 64% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2055 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2090, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: fkk9qmrfp9t22iefkri9eulstufk.jpg]](fkk9qmrfp9t22iefkri9eulstufk.jpg)

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity** | **94.00%** |
| U.S. Large Cap Equity  | 46.06% |
| U.S. Mid Cap Equity | 6.58% |
| U.S. Small Cap Equity  | 5.64% |
| REITs  | 1.88% |
| International Equity  | 24.91% |
| Emerging Markets Equity  | 8.93% |
| **Fixed Income** | **6.00%** |
| U.S. Fixed Income | 4.80% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income | 0.85% |
| Emerging Markets Debt | 0.35% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2090. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MassMutual Equity Opportunities Fund | 6.06% |
| MM Equity Asset Fund | 20.47% |
| MassMutual Blue Chip Growth Fund | 6.76% |
| MassMutual Overseas Fund | 9.27% |
| MassMutual International Equity Fund | 5.60% |
| Vanguard Developed Markets Index Fund | 7.91% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 6.40% |

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Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Service Class shares. The table shows how the Fund's average annual returns for 1 and 5 years, and since inception, compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Performance for Class I, Class R5, Class R4, and Class R3 shares of the Fund for periods prior to their inception date (04/01/14) is based on the performance of Service Class shares, adjusted for Class R4 and Class R3 shares to reflect Class R4 and Class R3 expenses, respectively. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Service Class Shares
![[MISSING IMAGE: e3kkrnv4slduuh9igmoup0ldl39r.jpg]](e3kkrnv4slduuh9igmoup0ldl39r.jpg)

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 17.88% | Lowest <br>Quarter: | 1Q '20,  | –22.24% |

---

After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through

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tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class only. After-tax returns for other classes will vary.

#### Average Annual Total Returns
(for the periods ended December 31, 2022)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years** | **Since <br>Inception <br>(09/17/13)**  |
| Service Class  | Return Before <br> Taxes  | -17.21% | 5.03% | 6.52% |
| Service Class  | Return After Taxes on Distributions | -19.74% | 2.19% | 4.37% |
| Service Class  | Return After Taxes on Distributions and Sales of Fund Shares | -8.44% | 3.70% | 4.92% |
| Class I | Return Before <br> Taxes | -16.98% | 5.25% | 6.69% |
| Class R5 | Return Before <br> Taxes | -17.04% | 5.14% | 6.58% |
| Administrative <br> Class | Return Before <br> Taxes | -17.28% | 4.93% | 6.41% |
| Class R4 | Return Before <br> Taxes | -17.40% | 4.78% | 6.23% |
| Class A | Return Before <br> Taxes | -21.95% | 3.52% | 5.52% |
| Class R3 | Return Before <br> Taxes | -17.62% | 4.51% | 5.96% |
| S&P Target Date 2055 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2055 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -15.97% | 5.31% | 8.46% |

---

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (September 2013).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2060 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

---

**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses | 0.95% | 1.05% | 1.15% | 1.25% | 1.15% | 1.25% | 1.15% |
|  Acquired Fund Fees and Expenses  | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% | 0.51% |
|  **Total Annual Fund Operating Expenses<sup>(1)</sup>**  | **1.46%**  | **1.56%**  | **1.66%**  | **1.76%**  | **1.91%**  | **2.01%**  | **2.16%**  |
| Expense Reimbursement | (0.95%) | (0.95%) | (0.95%) | (0.95%) | (0.95%) | (0.95%) | (0.95%) |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.51% | 0.61% | 0.71% | 0.81% | 0.96% | 1.06% | 1.21% |

---

(1) Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the "Financial Highlights" tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.00%, 0.10%, 0.20%, 0.30%, 0.45%, 0.55%, and 0.70% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| | **1 Year**  | **3 Years**  | **5 Years**  | **10 Years**  |
| Class I | $52 | $368 | $707 | $1665 |
| Class R5 | $62 | $399 | $760 | $1776 |
| Service Class | $73 | $430 | $813 | $1886 |
|  Administrative <br>Class  | $83 | $461 | $865 | $1994 |
| Class R4 | $98 | $508 | $943 | $2155 |
| Class A | $652 | $1059 | $1490 | $2687 |
| Class R3 | $123 | $584 | $1072 | $2418 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 78% of the average value of its portfolio.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2060 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's

specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2095, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

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The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's

strategic target allocations based on its position along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: raesjvt6el6esm3id37mmaj82nmc.jpg]](raesjvt6el6esm3id37mmaj82nmc.jpg)

---

| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity** | **94.00%** |
| U.S. Large Cap Equity  | 46.06% |
| U.S. Mid Cap Equity | 6.58% |
| U.S. Small Cap Equity  | 5.64% |
| REITs  | 1.88% |
| International Equity  | 24.91% |
| Emerging Markets Equity  | 8.93% |
| **Fixed Income** | **6.00%** |
| U.S. Fixed Income | 4.80% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income | 0.85% |
| Emerging Markets Debt | 0.35% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending

behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase.

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The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2095. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include

such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount

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for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's approximate allocation, as of January 11, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different

Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

---

| | |
|:---|:---|
| MassMutual Equity Opportunities Fund | 5.96% |
| MM Equity Asset Fund | 20.58% |
| MassMutual Blue Chip Growth Fund | 6.76% |
| MassMutual Overseas Fund | 9.27% |
| MassMutual International Equity Fund | 5.62% |
| Vanguard Developed Markets Index Fund | 7.88% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund | 6.41% |

---

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust

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various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected.

ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

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***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the

values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with

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the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody

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and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose

money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's

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investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more

rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer.

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In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk

and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for

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securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The following bar chart and table provide some indication of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year to year for Class I shares. The table shows how the Fund's average annual returns for 1 and 5 years, and since inception, compare with those of a broad measure of market performance. The Fund's name and investment strategy changed on September 24, 2018. The performance results shown below would not necessarily have been achieved had the Fund's current investment strategy been in effect for the entire period for which performance results are presented. Performance for Class A shares of the Fund reflects any applicable sales charge. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More up-to-date performance information is available at https://www.massmutual.com/funds or by calling 1-888-309-3539.

#### Annual Performance

#### Class I Shares
![[MISSING IMAGE: p8gch4k3bhpq3bfrsqi4uu70ftbl.jpg]](p8gch4k3bhpq3bfrsqi4uu70ftbl.jpg)

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| Highest <br>Quarter: | 2Q '20,  | 17.79% | Lowest <br>Quarter: | 1Q '20,  | –22.16% |

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After-tax returns are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class I only. After-tax returns for other classes will vary.

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#### Average Annual Total Returns
(for the periods ended December 31, 2022)

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| | | | | |
|:---|:---|:---|:---|:---|
|  |  | **One <br>Year**  | **Five <br>Years** | **Since <br>Inception <br>(11/23/15)**  |
| Class I  | Return Before <br> Taxes  | -16.97% | 5.25% | 7.20% |
| Class I  | Return After Taxes on Distributions | -19.64% | 2.31% | 4.62% |
| Class I  | Return After Taxes on Distributions and Sales of Fund Shares | -8.28% | 3.80% | 5.34% |
| Class R5 | Return Before <br> Taxes | -17.15% | 5.10% | 7.06% |
| Service Class  | Return Before <br> Taxes | -17.11% | 5.04% | 6.98% |
| Administrative <br> Class | Return Before <br> Taxes | -17.23% | 4.92% | 6.87% |
| Class R4 | Return Before <br> Taxes | -17.36% | 4.76% | 6.71% |
| Class A | Return Before <br> Taxes | -22.05% | 3.46% | 5.74% |
| Class R3 | Return Before <br> Taxes | -17.61% | 4.50% | 6.44% |
| S&P Target Date 2060 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | S&P Target Date 2060 Index <br> (reflects no deduction for fees, <br> expenses, or taxes) | -16.01% | 5.35% | 8.50% |

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#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since February 2023.

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio

manager at MML Advisers. He has managed the Fund since its inception (November 2015).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since September 2018.

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since February 2020.

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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MassMutual RetireSMART<sup>SM</sup> by JPMorgan 2065 Fund

#### INVESTMENT OBJECTIVE
The Fund seeks total return through its asset allocation, which is designed to become more conservative over time. As the Fund approaches and passes the target retirement date, the Fund's objective will shift to seeking current income and some capital appreciation.

#### FEES AND EXPENSES OF THE FUND
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. For Class A shares, you may qualify for sales charge discounts if you invest, or agree to invest in the future, at least $25,000 in MassMutual funds. More information about these and other discounts is available in the section titled *Sales Charges by Class* beginning on page 215 of the Fund's Prospectus or from your financial professional.

#### Shareholder Fees (fees paid directly from your investment)

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| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
|  Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)  |  |  |  |  |  | 5.50%  |  |
|  Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)  |  |  |  |  |  |  |  |

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**Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment)

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| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| | **Class I**  | **Class R5**  | **Service <br>Class**  | **Administrative <br>Class**  | **Class R4**  | **Class A**  | **Class R3**  |
| Management Fees | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  |
|  Distribution and Service (Rule 12b-1) Fees  |  |  |  |  | 0.25%  | 0.25%  | 0.50%  |
| Other Expenses<sup>(1)</sup> | 5.16%  | 5.26%  | 5.36%  | 5.46%  | 5.36%  | 5.46%  | 5.36%  |
|  Acquired Fund Fees and Expenses<sup>(1)</sup>  | 0.48%  | 0.48%  | 0.48%  | 0.48%  | 0.48%  | 0.48%  | 0.48%  |
|  **Total Annual Fund Operating Expenses**  | **5.64%**  | **5.74%**  | **5.84%**  | **5.94%**  | **6.09%**  | **6.19%**  | **6.34%**  |
| Expense Reimbursement | (5.16%)  | (5.16%)  | (5.16%)  | (5.16%)  | (5.16%)  | (5.16%)  | (5.16%)  |
|  Total Annual Fund Operating Expenses after Expense Reimbursement<sup>(2)</sup>  | 0.48%  | 0.58%  | 0.68%  | 0.78%  | 0.93%  | 1.03%  | 1.18%  |

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(1) Other Expenses and Acquired Fund Fees and Expenses are based on estimated amounts for the current fiscal year of the Fund.

(2) The expenses in the above table reflect a written agreement by MML Advisers to cap the fees and expenses of the Fund (other than extraordinary legal and other expenses, Acquired Fund Fees and Expenses, interest expense, expenses related to borrowings, securities lending, leverage, taxes, and brokerage, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses, as applicable) through January 31, 2024, to the extent that Total Annual Fund Operating Expenses after Expense Reimbursement would otherwise exceed 0.00%, 0.10%, 0.20%, 0.30%, 0.45%, 0.55%, and 0.70% for Classes I, R5, Service, Administrative, R4, A, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers.

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#### Example
This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund's operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | |
|:---|:---|:---|
| | **1 Year**  | **3 Years**  |
| Class I | $49 | $1221 |
| Class R5 | $59 | $1249 |
| Service Class | $69 | $1278 |
| Administrative Class | $80 | $1306 |
| Class R4 | $95 | $1349 |
| Class A | $649 | $1851 |
| Class R3 | $120 | $1419 |

---

#### Portfolio Turnover
The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance.

#### INVESTMENTS, RISKS, AND PERFORMANCE

#### Principal Investment Strategies
The Fund is a "fund of funds" that seeks to achieve its investment objective by investing in a combination of U.S. domestic and international mutual funds ("Underlying Funds") using an asset allocation strategy designed for investors who plan to retire around the year 2065 (the target retirement year) and then withdraw their investment in the Fund over time throughout retirement. The Fund is advised by MML Investment Advisers, LLC ("MML Advisers") and subadvised by J.P. Morgan Investment Management Inc. ("J.P. Morgan"). J.P. Morgan has responsibility for determining the Fund's strategic asset allocation (its "glide path") and tactical asset allocation (adjusting the Fund's specific exposures in response to changes in market conditions). MML Advisers has overall responsibility for the Fund and for implementing those allocations through the selection of, and allocations to, Underlying Funds.

The Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until December 31, 2100, the target maturity year. The Fund assumes a person will be at or around age 65 at the target retirement year.

Underlying Funds will include a combination of MassMutual Funds advised by MML Advisers and J.P. Morgan Funds advised by J.P. Morgan or its affiliates, and may also include other, non-affiliated mutual funds. Underlying Funds may invest in various asset classes, including equity securities, fixed income securities, and money market instruments. Underlying Funds may also invest some or all of their assets in commodities or commodities-related investments. The Fund will typically invest 80% or more of its assets in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, including typically a 15% to 35% allocation to mutual funds advised or subadvised by J.P. Morgan or its affiliates. Non-affiliated Underlying Funds in which the Fund may invest are typically passively managed funds that seek to track the performance of a particular market index, which may be broad-based or relate to a particular sector, market, region, or industry.

The Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, the Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, the Fund will generally have a greater emphasis on fixed income investments. Because the Fund is a number of years from the beginning of its Spending Phase, its portfolio reflects a greater emphasis on equity investments and less emphasis on fixed income investments than a similar fund whose Spending Phase will begin sooner.

The anticipated strategic target allocations between asset classes over the life of the Fund are displayed in the "glide path" below. In addition, the Fund's strategic target allocations based on its position

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along the glide path as of February 1, 2023 are included in the table following the glide path.

![[MISSING IMAGE: ai3np3cb9aoogh31vmc1n4a785vt.jpg]](ai3np3cb9aoogh31vmc1n4a785vt.jpg)

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| | |
|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** |  |
| **Equity** | **94.00%** |
| U.S. Large Cap Equity  | 46.06% |
| U.S. Mid Cap Equity | 6.58% |
| U.S. Small Cap Equity  | 5.64% |
| REITs  | 1.88% |
| International Equity  | 24.91% |
| Emerging Markets Equity  | 8.93% |
| **Fixed Income** | **6.00%** |
| U.S. Fixed Income | 4.80% |
| Inflation Managed | 0.00% |
| High Yield Fixed Income | 0.85% |
| Emerging Markets Debt | 0.35% |
| **Money Market/Cash and Cash Equivalents** | **0.00%** |
| Money Market/Cash and Cash Equivalents | 0.00% |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The Fund's actual allocations at any time will likely differ from those shown in the glide path and table above due to a number of factors, including, among others, changes made by J.P. Morgan to those strategic target allocations or changes arising from tactical allocations of the Fund's investments, cash flows into and out of the Fund, and appreciation/depreciation of the Fund's investments in different asset classes.

J.P. Morgan will periodically assess the strategic target allocations shown above, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending behavior of investors. Based on J.P. Morgan's

assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as the Fund moving along its glide path each year, the Fund's actual allocations may differ from the strategic target allocations shown above by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of the Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

During the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount as a consideration in determining how much of their investment to withdraw each year during the Spending Phase. The sample withdrawal amount will be made

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available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

As investors withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Fund's Board of Trustees ("Trustees"), without shareholder approval, at or prior to the target maturity year. J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the year 2100. As a result, the Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from the Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in the Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of the Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in the Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of the Fund from such account will need to include such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not consider the Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in the Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in the Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, the Fund specifically, including the Underlying Funds in which the Fund invests, or an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Internal Revenue Code of 1986, as amended (the "Code"), with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in the Fund would be exhausted before then.

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The Fund will normally invest most of its assets in Underlying Funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (which may include a fund or funds subadvised by J.P. Morgan); the Fund will normally invest no more than 20% of its assets in mutual funds not advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan (referred to here as "non-affiliated" funds). MML Advisers will select Underlying Funds from among mutual funds advised by it or J.P. Morgan or its affiliates even though they may have higher expense ratios or less favorable historical performance than non-affiliated funds, and MML Advisers will have no obligation to select the least expensive or best performing funds available to serve as Underlying Funds. In addition, MML Advisers will likely seek to invest assets in funds advised or subadvised by J.P. Morgan or its affiliates in an amount sufficient to ensure an appropriate level of revenue to J.P. Morgan. J.P. Morgan will be subject to a conflict of interest in determining the Fund's assets allocations, because it might expect to benefit financially by allocating the Fund's assets to asset classes where MML Advisers would be likely to invest in mutual funds advised or subadvised by J.P. Morgan or its affiliates. These conflicts of interest may result in a portfolio of Underlying Funds that achieves a level of performance, or incurs higher fees, less favorable to the Fund than if MML Advisers or J.P. Morgan did not consider such factors or were not subject to such conflicts of interest. There may be circumstances where MML Advisers' possession of non-public information regarding an Underlying Fund will limit the ability of the Fund to buy or sell shares in that Underlying Fund when it might otherwise do so, which might adversely affect the investment performance of the Fund.

The table below shows the Fund's expected approximate allocation, as of February 1, 2023, to Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under "Additional Information Regarding Investment Objectives and Principal Investment Strategies" in the Fund's Prospectus. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Fund's assets in additional or different Underlying Funds, including Funds that may be created in the future. At any given time, the Fund's allocations to Underlying Funds may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). Information regarding the

Fund's actual allocations to Underlying Funds is available in the Fund's shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is included in Appendix D of the Statement of Additional Information ("SAI").

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| | |
|:---|:---|
| MassMutual Equity Opportunities Fund | 6.86% |
| MM Equity Asset Fund | 20.00% |
| MassMutual Blue Chip Growth Fund | 6.72% |
| MassMutual Overseas Fund | 9.82% |
| MassMutual International Equity Fund | 6.14% |
| Vanguard Developed Markets Index Fund | 8.59% |

---

Through its investments in Underlying Funds, the Fund will be exposed to a wide range of securities and other instruments with differing characteristics (such as credit quality, duration, geography, industry, and market capitalization), which may include without limitation equity securities of small-, mid-, or large-capitalization U.S. or non-U.S. issuers (including issuers that may only recently have become public companies), fixed income securities of U.S. or non-U.S. private or governmental issuers (including "junk" or "high yield" bonds, including securities in default), inflation-protected securities, bank loans, and short-term investments of any kind. Equity securities may include common stocks, preferred stocks, securities convertible into common or preferred stock, real estate investment trusts ("REITs"), rights, and warrants. An Underlying Fund may engage in foreign currency exchange transactions, including forward contracts, options on currency, futures contracts, and swap contracts, to take long or short positions in foreign currencies in order to enhance its investment return or to attempt to protect against adverse changes in currency exchange rates. An Underlying Fund may be permitted to use a wide variety of additional exchange-traded and over-the-counter derivatives, including options, futures contracts, swap contracts (including interest rate swaps, total return swaps, and credit default swaps), and hybrid instruments. An Underlying Fund may typically use these derivatives for hedging purposes, as a substitute for direct investments, to earn additional income, to gain exposure to securities or markets in which it might not be able to invest directly, or to adjust various portfolio characteristics, including the duration (interest rate volatility) of the Fund's portfolio of debt securities. Use of derivatives by an Underlying Fund may create investment leverage. An Underlying Fund may enter into repurchase agreement transactions. An Underlying Fund may invest in mortgage-backed or other asset-backed securities. An Underlying Fund may enter into

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dollar roll or reverse repurchase agreement transactions. Some investments by an Underlying Fund may be restricted as to resale or otherwise considered to be illiquid. An Underlying Fund may engage in active and frequent trading and so could have a relatively high portfolio turnover rate. The Fund will bear a pro rata share of the Underlying Funds' expenses. The Fund also bears all of the risks associated with the investment strategies used by the Underlying Funds.

#### Principal Risks
The following are the Principal Risks of the Fund. An investment in this Fund is not guaranteed. The value of your investment in the Fund could go down as well as up. You can lose money by investing in the Fund, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate income at and through your retirement. Although the descriptions below refer to the risks relating to investment activities of the Fund, many of the risks arise due to the investment activities of the Underlying Funds. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

***Allocation Risk*** There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of Fund assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan as noted in "Principal Investment Strategies" may adversely affect Fund performance.

***Risk of Investment in Other Funds or Pools*** The Fund is indirectly exposed to all of the risks of the Underlying Funds, including exchange-traded funds, in which it invests, including the risk that the Underlying Funds will not perform as expected. ETFs are subject to additional risks, including secondary market trading risks and the risk that an ETF's shares may trade above or below net asset value. The Fund indirectly pays a portion of the expenses incurred by the Underlying Funds.

***Tactical Allocation Risk*** The subadviser has discretion to make short- to intermediate-term

tactical allocations that increase or decrease the exposure to asset classes and investments shown in the glide path. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in the glide path from time to time.

***Bank Loans Risk*** Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. Senior secured bank loans are typically supported by collateral; however the value of the collateral may be insufficient to cover the amount owed to the Fund, or the Fund may be prevented or delayed from realizing on the collateral. Some loans may be unsecured; unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. If the Fund relies on a third party to administer a loan, the Fund is subject to the risk that the third party will fail to perform its obligations. In addition, if the Fund holds only a participation interest in a loan made by a third party, the Fund's receipt of payments on the loan will depend on the third party's willingness and ability to make those payments to the Fund. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of readily at what the Fund believes to be a fair price. Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

***Below Investment Grade Debt Securities Risk*** Below investment grade debt securities, commonly known as "junk" or "high yield" bonds, have speculative characteristics and involve greater volatility of price and yield, greater risk of loss of principal and interest, and generally reflect a greater possibility

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of an adverse change in financial condition that could affect an issuer's ability to honor its obligations.

***Cash Position Risk*** If the Fund holds a significant portion of its assets in cash or cash equivalents, its investment returns may be adversely affected and the Fund may not achieve its investment objective.

***China Investment Risk*** Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, such as greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, and the risk of nationalization or expropriation of assets. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries.

***Commodities-Related Investments Risk*** Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the net asset value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political, and regulatory developments, or factors affecting a particular region, industry, or commodity. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

***Convertible Securities Risk*** Convertible securities are subject to the risks of both debt instruments and equity securities. The price of a convertible security may change in response to changes in price of the underlying equity security, the credit quality of the issuer, and interest rates. In general, the values of convertible securities tend to decline as interest rates rise and to rise when interest rates fall. A convertible security generally has less potential for gain or loss than the underlying equity security.

***Credit Risk*** Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income

security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances.

***Defaulted and Distressed Securities Risk*** Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is uncertain. To the extent the Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

***Derivatives Risk*** Derivatives can be highly volatile and involve risks different from, and potentially greater than, direct investments, including risks of imperfect correlation between the value of derivatives and underlying assets, counterparty default, potential losses that partially or completely offset gains, and illiquidity. Derivatives can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. If the value of a derivative does not correlate well with the particular market or asset class the derivative is designed to provide exposure to, the derivative may not have the effect or benefit anticipated. Derivatives can also reduce the opportunity for gains or result in losses by offsetting positive returns in other investments. Many derivatives are traded in the over-the-counter market and not on exchanges.

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***Dollar Roll and Reverse Repurchase Agreement Transaction Risk*** These transactions generally create leverage and subject the Fund to the credit risk of the counterparty.

***Equity Securities Risk*** Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

***Fixed Income Securities Risk*** The values of fixed income securities typically will decline during periods of rising interest rates, and can also decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral assets, or changes in market, economic, industry, political, regulatory, public health, and other conditions affecting a particular type of security or issuer or fixed income securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, and potentially at unfavorable prices. Certain securities may be difficult to value during such periods. Fixed income securities are subject to interest rate risk (the risk that the value of a fixed income security will fall when interest rates rise), extension risk (the risk that the average life of a security will be extended through a slowing of principal payments), prepayment risk (the risk that a security will be prepaid and the Fund will be required to reinvest at a less favorable rate), duration risk (the risk that longer-term securities may be more sensitive to interest rate changes), inflation risk (the risk that as inflation increases, the present value of the Fund's fixed income investment typically will decline), and credit risk.

***Foreign Investment Risk; Emerging Markets Risk; Currency Risk*** Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other

conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, the Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of the Fund (or clients of the Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the U.S. The securities of some non-U.S. companies, especially those in emerging markets, are less liquid and at times more volatile than securities of comparable U.S. companies. Emerging markets securities are subject to greater risks than securities issued in developed foreign markets, including less liquidity, less stringent investor protection and disclosure standards, less reliable settlement practices, greater price volatility, higher relative rates of inflation, greater political, economic, and social instability, greater custody and operational risks, greater risk of new or inconsistent government treatment of or restrictions on issuers and instruments, and greater volatility in currency exchange rates, and are more susceptible to environmental problems. Many emerging market countries are highly reliant on

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international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity. Non-U.S. transaction costs, such as brokerage commissions and custody costs, may be higher than in the United States. In addition, foreign markets can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

***Frequent Trading/Portfolio Turnover Risk*** Portfolio turnover generally involves some expense to the Fund and may result in the realization of taxable capital gains (including short-term gains). The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund's performance.

***Geographic Focus Risk*** When the Fund focuses investments on a particular country, group of countries, or geographic region, its performance will be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

***Growth Company Risk*** The prices of growth securities are often highly sensitive to market fluctuations because of their heavy dependence on future earnings or cash flow expectations, and can be more volatile than the market in general.

***Hedging Risk*** The Fund's attempts at hedging and taking long and short positions in currencies may not be successful and could cause the Fund to lose money or fail to get the benefit of a gain on a hedged position. If expected changes to securities prices, interest rates, currency values, and exchange rates, or the creditworthiness of an issuer are not accurately predicted, the Fund could be in a worse position than if it had not entered into such transactions.

***Index Funds Risk*** Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

***Inflation Risk*** The value of assets or income from the Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Inflation-Linked Securities Risk*** Such securities may change in value in response to actual or anticipated changes in inflation rates in a manner unanticipated by the Fund's portfolio manager or investors generally. Inflation-linked securities are subject to fixed income securities risks. When inflation is low, declining, or negative, the Fund's performance could lag the performance of more conventional bond funds. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors.

***Large Company Risk*** Large-capitalization stocks as a group could fall out of favor with the market, causing the Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization

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stocks. Larger, more established companies may be slow to respond to challenges and may grow more slowly than smaller companies.

***Liquidity Risk*** Certain securities may be difficult (or impossible) to sell or certain positions may be difficult to close out at a desirable time and price, and the Fund may be required to hold an illiquid investment that is declining in value, or it may be required to sell certain illiquid investments at a price or time that is not advantageous in order to meet redemptions or other cash needs. Some securities may be subject to restrictions on resale. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time. The Fund may not receive the proceeds from the sale of certain investments for an extended period.

***Management Risk*** The Fund relies on the manager's investment analysis and its selection of investments to achieve its investment objective. There can be no assurance that the Fund will achieve the intended results and the Fund may incur significant losses.

***Market Risk*** The value of the Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable market-induced changes affecting particular industries, sectors, or issuers. Stock and bond markets can decline significantly in response to issuer, market, economic, industry, political, regulatory, geopolitical, public health, and other conditions, as well as investor perceptions of these conditions. The Fund is subject to risks affecting issuers, such as management performance, financial leverage, industry problems, and reduced demand for goods or services.

***Maturity Date and Redemption Risk*** Even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. The Fund's assets will decline over time and reach zero on or before the maturity date. If the Fund's assets decline more rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As the Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment

objective. In addition, as assets in the Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, the Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for the Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

***Mortgage- and Asset-Backed Securities Risk*** Investments in mortgage- and asset-backed securities subject the Fund to credit risk, interest rate risk, extension risk, and prepayment risk, among other risks. Mortgage-backed and asset-backed securities not issued by a government agency generally involve greater credit risk than securities issued by government agencies. Payment of principal and interest generally depends on the cash flows generated by the underlying assets and the terms of the security. The types of mortgages (for example, residential or commercial mortgages) underlying securities held by the Fund may differ and be affected differently by market factors. Investments that receive only the interest portion or the principal portion of payments on the underlying assets may be highly volatile. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

***Preferred Stock Risk*** Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, changes in interest rates may adversely affect the value of a preferred stock that pays a fixed dividend. Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

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***Real Estate Risk; REIT Risk*** Real estate-related investments may decline in value as a result of factors affecting the real estate industry, such as the supply of real property in certain markets, changes in zoning laws, environmental regulations and other governmental action, delays in completion of construction, changes in real estate values, changes in property taxes, levels of occupancy, losses due to natural disasters, and local and regional market conditions. Investments in REITs may be subject to risks similar to those associated with direct investment in real estate, as well as additional risks associated with equity investments. As a shareholder in a REIT, the Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses.

***Repurchase Agreement Risk*** These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral.

***Sample Withdrawal Amount Risk*** The Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that the Fund will provide sufficient retirement income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in the Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in the Fund, you should be aware of the following:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in the Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and the Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk and return target of the Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of the Fund during the Spending Phase, but it may not be successful in doing so,

and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change the Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads the Fund to underperform (outperform) the long-term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long-term risk and return target in subsequent years. It is important that you re-evaluate your investment in the Fund periodically.

3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of the Fund. As a result, if you do not reinvest distributions and you withdraw from the Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in the Fund will be exhausted prior to the target maturity year.

***Sector Risk*** The Fund may allocate more of its assets to particular industries or to particular economic, market, or industry sectors than to others. This could increase the volatility of the Fund's portfolio, and the Fund's performance may be more susceptible to developments affecting issuers in those industries or sectors than if the Fund invested more broadly.

***Small and Mid-Cap Company Risk*** Market risk and liquidity risk are particularly pronounced for securities of small and medium-sized companies, which may trade less frequently and in smaller volumes than more widely-held securities, and may fluctuate in price more than other securities. Their shares can be less liquid than those of larger companies, especially during market declines. Small and medium-sized companies may have limited product lines, markets, or financial resources and may be dependent on a limited management

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group; they may have been recently organized and have little or no track record of success.

***Sovereign Debt Obligations Risk*** Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. Many sovereign debt obligations may be rated below investment grade ("junk" or "high yield" bonds). Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt.

***Stock Connect Risk*** The Fund may invest in China A Shares through Stock Connect, which is subject to sudden changes in quota limitations, application of trading suspensions, price fluctuations during times when Stock Connect is not trading, operational risk, clearing and settlement risk, and regulatory and taxation risk.

***U.S. Government Securities Risk*** Obligations of certain U.S. Government agencies and instrumentalities are not backed by the full faith and credit of the U.S. Government, and there can be no assurance that the U.S. Government would provide financial support to such agencies and instrumentalities.

***Valuation Risk*** The Fund is subject to the risk of mispricing or improper valuation of its investments, in particular to the extent that its securities are fair valued.

***Value Company Risk*** The value investment approach entails the risk that the market will not recognize a security's intrinsic value for a long time, or that a stock the investment adviser or subadviser judges to be undervalued may actually be appropriately priced.

***When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk*** These transactions may create leverage and involve a risk of loss if the value of the securities declines prior to settlement.

#### Performance Information
The Fund had not begun operations prior to the date of this Prospectus, and therefore has no performance history. Because the Fund is new, there is no table which shows how the Fund's returns have deviated from the broad market. Performance history will be available for the Fund after it has been in operation for one calendar year.

#### MANAGEMENT
**Investment Adviser:** MML Investment Advisers, LLC ("MML Advisers")

**Subadviser(s):** J.P. Morgan Investment Management Inc. ("J.P. Morgan")

#### Portfolio Manager(s):
**Michael J. Abata, CFA** is a portfolio manager at MML Advisers. He has managed the Fund since its inception (February 2023).

**Frederick (Rick) Schulitz, CFA, CAIA** is Head of Multi-Asset Class Solutions and a portfolio manager at MML Advisers. He has managed the Fund since its inception (February 2023).

**Daniel Oldroyd, CFA, CAIA** is a Managing Director, the Head of Target Date Strategies, and a portfolio manager at J.P. Morgan. He has managed the Fund since its inception (February 2023).

**Silvia Trillo** is a Managing Director and portfolio manager at J.P. Morgan. She has managed the Fund since its inception (February 2023).

#### PURCHASE AND SALE OF FUND SHARES
Shares of the Fund are generally available to retirement plans, other institutional investors, and individual retirement accounts. Fund shares are redeemable on any business day by written request, telephone, or internet (available to certain customers).

#### TAX INFORMATION
The Fund intends to make distributions that may be taxed as ordinary income, qualified dividend income, or capital gains, unless you are an investor eligible for preferential tax treatment.

#### PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES
If you purchase the Fund through a broker-dealer or other financial intermediary, the intermediary may receive a one-time or continuing payments

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from the Fund, MML Advisers or its affiliates, or others for the sale of Fund shares or continuing shareholder services provided by the intermediary. These payments may create a conflict of interest by influencing the broker-dealer or other

intermediary to recommend the Fund over another investment. You should contact your intermediary to obtain more information about the compensation it may receive in connection with your investment.

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Additional Information Regarding Investment Objectives and Principal Investment Strategies

Except as otherwise stated, references in this section to "the Funds" or "a Fund" may relate to the Fund, one or more Underlying Funds, or both.

#### Changes to Investment Objectives and Strategies.
Each MassMutual Target Allocation Fund's and MassMutual RetireSMART by JPMorgan Fund's investment objective and strategies are non-fundamental and may be changed by the Board of Trustees (the "Trustees") of the MassMutual Select Funds (the "Trust") without shareholder approval.

#### Note Regarding Percentage Limitations.
All percentage limitations on investments in this Prospectus will apply at the time of investment, and will not be considered violated unless an excess or deficiency occurs or exists immediately after and as a result of the investment. (As a result, the actual investments making up a Fund's portfolio may not at a particular time comport with any such limitation due to increases or decreases in the values of securities held by the Fund.) However, if, through a change in values, net assets, or other circumstances, a Fund were in a position where more than 15% of its net assets was invested in illiquid securities, the Fund would take appropriate orderly steps, as deemed necessary, to protect liquidity.

#### Credit Ratings.
Security ratings are determined at the time of investment based on ratings published by nationally recognized statistical rating organizations; if a security is not rated, it will be deemed to have the same rating as a security determined by the investment adviser or subadviser to be of comparable quality. Unless otherwise stated, if a security is rated by more than one nationally recognized statistical rating organization, the highest rating is used. The Fund may retain any security whose rating has been downgraded after purchase.

#### Duration.
Duration is a measure of the expected life of a debt security that is used to determine the sensitivity of the security's value to changes in interest rates. The longer a security's duration, the more sensitive it will be to changes in interest rates. For example, if interest rates rise by 1%, the value of a debt security with a duration of two

years would be expected to decline 2% and the value of a debt security with a duration of four years would be expected to decline 4%. Unlike the maturity of a debt security, which measures only the time until final payment is due, duration takes into account the time until all payments of interest and principal on a security are expected to be made, including how these payments are affected by prepayments and by changes in interest rates. Determining duration may involve estimates of future economic parameters, which may vary from actual future values.

#### Leverage.
Leverage generally has the effect of increasing the amount of loss or gain a Fund might realize, and may increase volatility in the value of a Fund's investments. Adverse changes in the value or level of the underlying asset, rate, or index may result in a loss substantially greater than the amount invested in the derivative itself.

#### Temporary Defensive Positions.
At times, a Fund's investment adviser or subadviser may determine that market conditions make pursuing a Fund's basic investment strategy inconsistent with the best interests of its shareholders. At such times, the investment adviser or subadviser may (but will not necessarily), without notice, temporarily use alternative strategies primarily designed to reduce fluctuations in the values of a Fund's assets. In implementing these defensive strategies, a Fund may hold assets without limit in cash and cash equivalents and in other investments that the investment adviser or subadviser believes to be consistent with the Fund's best interests. If such a temporary defensive strategy is implemented, a Fund may not achieve its investment objective.

#### Portfolio Turnover.
Changes are made in a Fund's portfolio whenever the investment adviser or subadviser believes such changes are desirable. Portfolio turnover rates are generally not a factor in making buy and sell decisions. A high portfolio turnover rate will result in higher costs from brokerage commissions, dealer-mark-ups, bid-ask spreads, and other transaction costs and may also result in a higher percentage of short-term capital gains and a lower percentage of long-term capital gains as compared to a fund that trades less frequently (short-term

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capital gains generally receive less favorable tax treatment in the hands of shareholders than do long-term capital gains). Such costs are not reflected in the Funds' Total Annual Fund Operating Expenses set forth in the fee tables but do have the effect of reducing a Fund's investment return.

#### Non-Principal Investments; Use of Derivatives; Repurchase Agreements.
A Fund may hold investments that are not included in its principal investment strategies. These non-principal investments are described in the SAI or below under "Additional Information Regarding Principal Risks." A Fund also may choose not to invest in certain securities described in this Prospectus and in the SAI, even though it has the ability to do so. Certain Funds may engage in transactions involving derivatives as part of their principal investment strategies; the disclosures of the principal investment strategies of those Funds include specific references to those derivatives transactions. Any of the other Funds may engage in derivatives transactions not as part of their principal investment strategies, and Funds that may use certain derivatives as part of their principal investment strategies may use other derivatives (not as part of their principal investment strategies), as well. A Fund may use derivatives for hedging purposes, as a substitute for direct investment, to earn additional income, to adjust portfolio characteristics, including duration (interest rate volatility), to gain exposure to securities or markets in which it might not be able to invest directly, to provide asset/liability management, or to take long or short positions on one or more indexes, securities, or foreign currencies. If a Fund takes a short position with respect to a particular index, security, or currency, it will lose money if the index, security, or currency appreciates in value, or an expected credit or other event that might affect the value of the index, security, or currency fails to occur. Losses could be significant. Derivatives transactions may include, but are not limited to, foreign currency exchange transactions, options, futures contracts, interest rate swaps, interest rate futures contracts, forward contracts, total return swaps, credit default swaps, and hybrid instruments. A Fund may use derivatives to create investment leverage. See "Additional Information Regarding Principal Risks," below, and the SAI for more information regarding those transactions.

A Fund may enter into repurchase agreements, and an Underlying Fund may make loans of portfolio securities to broker-dealers and other financial intermediaries of up to 33⅓% of its total

assets. These transactions must be fully collateralized at all times, but involve some risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral, or if the Fund is required to return collateral to a borrower at a time when it may realize a loss on the investment of that collateral. A repurchase agreement is a transaction in which a Fund purchases a security from a seller, subject to the obligation of the seller to repurchase that security from the Fund at a higher price. A Fund may enter into repurchase agreements as a non-principal investment strategy.

#### Foreign Securities.
The globalization and integration of the world economic system and related financial markets have made it increasingly difficult to define issuers geographically. Accordingly, the Funds and other series of the Trust and series of MassMutual Funds intend to construe geographic terms such as "foreign," "non-U.S.," "European," "Latin American," "Asian," and "emerging markets" in the manner that affords to the Funds and other series the greatest flexibility in seeking to achieve the investment objective(s) of the relevant series. Specifically, unless otherwise stated, in circumstances where the investment objective and/or strategy is to invest (a) exclusively in "foreign securities," "non-U.S. securities," "European securities," "Latin American securities," "Asian securities," or "emerging markets" (or similar directions) or (b) at least some percentage of the Fund's or other series assets in foreign securities, etc., the Fund or other series will take the view that a security meets this description so long as the issuer of a security is tied economically to the particular country or geographic region indicated by words of the relevant investment objective and/or strategy (the "Relevant Language"). For these purposes the issuer of a security is deemed to have that tie if:

(i) the issuer is organized under the laws of the country or a country within the geographic region suggested by the Relevant Language or maintains its principal place of business in that country or region; or

(ii) the securities are traded principally in the country or region suggested by the Relevant Language; or

(iii) the issuer, during its most recent fiscal year, derived at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in the country or region

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suggested by the Relevant Language or has at least 50% of its assets in that country or region.

In addition, the Funds and other series intend to treat derivative securities (e.g., call options) for this purpose by reference to the underlying security. Conversely, if the investment objective and/or strategy of a series limits the percentage of assets that may be invested in "foreign securities," etc. or prohibits such investments altogether, a series intends to categorize securities as "foreign," etc. only if the security possesses all of the attributes described above in clauses (i), (ii), and (iii).

#### MassMutual RetireSMART by JPMorgan Funds.
Each MassMutual RetireSMART by JPMorgan Fund invests its assets in a combination of Underlying Funds providing U.S. domestic and international investment exposures. The various MassMutual RetireSMART by JPMorgan Funds differ among themselves primarily due to their asset allocations among these fund types.

Each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name uses an asset allocation strategy designed for investors who plan to retire around the year specified in its name (the target retirement year) and then withdraw their investment in the Fund over time. Each Fund seeks to help investors save for retirement and then, after reaching the target retirement year, withdraw a portion of their investment in the Fund each year until 35 years after the target retirement year, the target maturity year. Each Fund assumes a person will be at or around age 65 at the target retirement year. Each Fund's asset allocation strategy is designed with two main goals in mind: promoting asset accumulation prior to retirement, during the Fund's "Savings Phase," and supporting investors withdrawing their investments in the Fund throughout retirement, during the Fund's "Spending Phase." As a result, a Fund's asset allocation strategy will change over time, generally becoming more conservative as it approaches the target retirement year and then remaining relatively stable afterwards. The asset allocation strategy during the Savings Phase will generally start with a greater emphasis on equity investments and gradually shift to more emphasis on fixed income investments. During the Spending Phase, a Fund will generally have a greater emphasis on fixed income investments.

The MassMutual RetireSMART by JPMorgan In Retirement Fund uses an asset allocation strategy designed for investors who are retired or expect

to retire soon. The Fund's assets are allocated among Underlying Funds according to an asset allocation strategy that emphasizes fixed income and money market funds, but also includes smaller allocations to equity and certain other funds.

As investors in each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name withdraw their investments in the Fund over time during the Spending Phase, the Fund's assets are expected to decline over time and approach zero in the target maturity year. As assets decline and approach zero, there may be a point before the target maturity year where MML Advisers can no longer manage the Fund in line with its investment goal. In such a case, it is expected that the Fund would be liquidated or merged into the MassMutual RetireSMART by JPMorgan In Retirement Fund at the discretion of the Trustees, without shareholder approval, at or prior to the target maturity year. Shareholders of each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name will be notified in writing prior to its liquidation or its combination with the MassMutual RetireSMART by JPMorgan In Retirement Fund.

#### Glide Path.
J.P. Morgan uses a strategic asset allocation strategy for each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name that changes over time as a Fund approaches its target retirement year. This is known as the "glide path." As a MassMutual RetireSMART by JPMorgan Fund approaches and passes its target retirement year, the investment objective for the Fund shifts from seeking total return to current income and some capital appreciation. It is intended that, by the end of its target retirement year, each Fund's strategic target allocations will approximate those of the MassMutual RetireSMART by JPMorgan In Retirement Fund.

Each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name is a "to" fund rather than a "through" fund. A "through" target date fund has a longer glide path that goes beyond the retirement year. "Through" funds are designed for investors with longer investment horizons that go 10 to 20 years past their retirement age. These funds are generally more aggressive in their strategic target allocations to equities at retirement than "to" funds, and become more conservative over a longer period of

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time after retirement. A "to" target date fund generally treats the target date as the end point of the glide path. These funds generally reach their most conservative strategic target allocations close to the target retirement date. Each MassMutual RetireSMART by JPMorgan Fund with a specified target retirement year in its name is a "to" target date fund and is designed for investors who are seeking current income and some capital appreciation rather than continuing to seek total return on their retirement date.

#### Strategic Target Allocations.
J.P. Morgan will periodically assess the Funds' strategic target allocations, and may make adjustments to them, taking into account various factors, such as current market conditions, assumptions regarding future market performance, time horizon, and data on the savings and spending behavior of investors. Based on J.P. Morgan's assessment, these adjustments may include modifying the existing allocations among asset classes or, among other things, adding or removing asset classes or maintaining asset allocations for longer or shorter periods of time. As a result of J.P. Morgan's ability to make these modifications, as well as a Fund moving along its glide path each year, as applicable, a MassMutual RetireSMART by JPMorgan Fund's actual allocations may differ from the strategic target allocations by as much as +/- 15%. In addition, as J.P. Morgan monitors the risk profile of a Fund in various market environments, it may determine that conditions are not favorable and that deviations beyond +/- 15% are necessary to substantially reduce risk in order to preserve capital.

For those MassMutual RetireSMART by JPMorgan Funds with a specified target retirement year in their name, during the Spending Phase, J.P. Morgan will seek to achieve certain long-term risk and return targets that allow investors to withdraw a portion of their investment in the Fund each year until the target maturity year. In connection with this, J.P. Morgan will produce at the beginning of each year an annual "sample withdrawal amount." The sample withdrawal amount is a generic hypothetical example that seeks to estimate a percentage of an investor's investment in the Fund as of the beginning of the year that theoretically could be redeemed by an investor during that year while still allowing for redemptions in future years through the target maturity year. It attempts to balance income needs in the current year against the need for income in the future. Investors may use the sample withdrawal amount

as a consideration in determining how much of their investment to withdraw each year during the Spending Phase. The sample withdrawal amount will be made available in January of each year at https://www.massmutual.com/funds, and by calling 888-309-3539.

J.P. Morgan anticipates that the sample withdrawal amount will increase as a percentage of an investor's investment over time prior to the target maturity year and that the sample withdrawal amount will be 100% of an investor's investment in the target maturity year. As a result, a Fund and the sample withdrawal amount will be less useful for those who invest closer to the target maturity year. The sample withdrawal amount is not expected to be level from year to year and instead will likely vary each year. If investors choose in a year to withdraw from a Fund an amount equal to the sample withdrawal amount for that year (or any other amount), they will be redeeming shares and their investment in a Fund will be reduced. Calculation of the sample withdrawal amount assumes the reinvestment of all distributions in additional shares of each Fund. If distributions are not reinvested and an investor nonetheless withdraws annually an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, there will be an increased likelihood that the investor will (i) have insufficient shares for redemption in future years and (ii) exhaust their assets in each Fund prior to the maturity year.

In addition, the sample withdrawal amount is not designed to comply with any required minimum distribution rules applicable to tax deferred retirement accounts nor does it take into account any tax considerations to investors (including, for example, any early withdrawal penalties that may be imposed on investors in tax-deferred retirement accounts). Investors investing through a tax-deferred retirement account subject to a required minimum distribution who redeem shares of a Fund from such account will need to include such redemption amount, as appropriate, in the computation of any annual required minimum distribution.

Many of the assumptions and factors underlying the sample withdrawal amount will be based on estimates and judgments by J.P. Morgan. If those estimates or judgments are inaccurate or incomplete, the withdrawal amount may not accurately reflect the amount that an investor could redeem during the year while still allowing for redemptions in future years. Investors should not

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consider a Fund a complete solution for their investment or retirement income needs or as a guarantee of income through the target maturity year or over any other period. In making a decision about their investments in a Fund in their individual situations, or in assessing the adequacy of estimated distributions that they may receive at any particular time, investors should consider all of their other assets, income, and investments in addition to their investment in a Fund, and should consult their retirement and tax advisers.

The provision of a sample withdrawal amount is for the purpose of outlining a possible theoretical course of action. The sample withdrawal amount is a generic hypothetical example as of a specific calculation date that does not consider, nor is it based upon, an investor's specific circumstances including their age, financial needs, risk tolerance, required minimum distribution amount under the Code, with respect to any year, if any, other assets, and overall investment objectives. The provision of a sample withdrawal amount is not a recommendation or suggestion that any particular redemption amount is advisable for any investor or in any investor's best interest, nor is it a

recommendation regarding any particular course of conduct in any particular situation or with respect to any particular investor. Instead, it will be presented merely for educational purposes so as to give an indication as to the kinds of approaches that may be possible, and each investor should make an independent decision regarding how to proceed based on their own independent analysis, taking into account whatever independent advice from the investor's professional adviser, tax adviser, or other third parties that the investor may regard as necessary or appropriate to obtain. There can be no assurance that, even if an investor redeems, in each year during the Spending Phase, shares in an amount equal to the sample withdrawal amount for that year, the assets in the investor's account will be sufficient to support distributions for the entire period through the target maturity year, and it is possible that the investor's account in a Fund would be exhausted before then.

The anticipated strategic target allocations between asset classes over the life of a Fund are displayed in the "glide path" below. The table following the glide path is simply the glide path in tabular form.

![[MISSING IMAGE: apk7narsfnm1tvhsvkij3c1msrp4.jpg]](apk7narsfnm1tvhsvkij3c1msrp4.jpg)

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| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | **Strategic Target Allocations<sup>(1)</sup>** | |
| **Years to Target Date**  | **40+**  | **35**  | **30**  | **25**  | **20**  | **15**  | **10**  | **5**  | **0**  | **-5**  | **-10**  | **-20**  | **-35**  |
| **Equity** | **94.00%**  | **94.00%**  | **94.00%**  | **94.00%**  | **87.00%**  | **78.00%**  | **65.95%**  | **53.00%**  | **40.00%**  | **40.00%**  | **40.00%**  | **40.00%**  | **40.00%**  |
| &nbsp;&nbsp;&nbsp; U.S. Large Cap Equity  | 46.00% | 46.00% | 46.00% | 46.00% | 42.65%  | 38.25%  | 32.35%  | 26.00% | 19.60%  | 19.60%  | 19.60%  | 19.60%  | 19.60%  |
| &nbsp;&nbsp;&nbsp; U.S. Mid Cap Equity  | 6.60%  | 6.60%  | 6.60%  | 6.60%  | 6.10%  | 5.45%  | 4.60%  | 3.70%  | 2.80%  | 2.80%  | 2.80%  | 2.80%  | 2.80%  |
| &nbsp;&nbsp;&nbsp; U.S. Small Cap Equity  | 5.65%  | 5.65%  | 5.65%  | 5.65%  | 5.20%  | 4.70%  | 3.95%  | 3.20%  | 2.40%  | 2.40%  | 2.40%  | 2.40%  | 2.40%  |
| &nbsp;&nbsp;&nbsp; REITs  | 1.90% | 1.90% | 1.90% | 1.90% | 1.75% | 1.55% | 1.30% | 1.05% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80%  |
| &nbsp;&nbsp;&nbsp; International Equity  | 24.90% | 24.90% | 24.90% | 24.90%  | 23.05%  | 21.05% | 17.80% | 14.30% | 11.20% | 11.20% | 11.20% | 11.20% | 11.20% |
| &nbsp;&nbsp;&nbsp; Emerging Markets Equity  | 8.95% | 8.95% | 8.95% | 8.95%  | 8.25% | 7.00% | 5.95% | 4.75% | 3.20% | 3.20% | 3.20%  | 3.20%  | 3.20%  |
| **Fixed Income** | **6.00%**  | **6.00%**  | **6.00%**  | **6.00%**  | **13.00%**  | **22.00%**  | **34.05%**  | **47.00%**  | **55.00%**  | **55.00%**  | **55.00%**  | **55.00%**  | **55.00%**  |
| &nbsp;&nbsp;&nbsp; U.S. Fixed Income  | 4.80%  | 4.80%  | 4.80%  | 4.80%  | 10.40%  | 17.60%  | 27.20%  | 34.60%  | 36.50% | 36.50%  | 36.50%  | 36.50%  | 36.50%  |
| &nbsp;&nbsp;&nbsp; Inflation Managed  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 3.00%  | 7.50%  | 7.50%  | 7.50%  | 7.50%  | 7.50%  |
| &nbsp;&nbsp;&nbsp; High Yield Fixed Income  | 0.85%  | 0.85%  | 0.85%  | 0.85%  | 2.20% | 3.75% | 5.80% | 8.00% | 9.35% | 9.35% | 9.35% | 9.35% | 9.35%  |
| &nbsp;&nbsp;&nbsp; Emerging Markets Debt  | 0.35%  | 0.35%  | 0.35%  | 0.35%  | 0.40% | 0.65% | 1.05% | 1.40% | 1.65% | 1.65% | 1.65% | 1.65% | 1.65%  |
|  **Money Market/Cash and Cash Equivalents**  | **0.00%**  | **0.00%**  | **0.00%**  | **0.00%**  | **0.00%**  | **0.00%**  | **0.00%**  | **0.00%**  | **5.00%**  | **5.00%**  | **5.00%**  | **5.00%**  | **5.00%**  |
| &nbsp;&nbsp;&nbsp; Money Market/Cash and Cash Equivalents  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 5.00%  | 5.00%  | 5.00%  | 5.00%  | 5.00%  |

---

(1) The Fund utilizes Underlying Funds to implement its strategic target allocations.

Note: Above allocations may not sum up to 100% due to rounding.

The following table lists the approximate allocation, as of January 11, 2023, for each of the MassMutual RetireSMART by JPMorgan Funds (other than the MassMutual RetireSMART by JPMorgan 2065 Fund) and the expected approximate allocation, as of February 1, 2023, for the MassMutual RetireSMART by JPMorgan 2065 Fund, to Underlying Funds in which a MassMutual RetireSMART by JPMorgan Fund invests 5% or more of its assets. Other Underlying Funds in which the MassMutual RetireSMART by JPMorgan Funds invest are listed below the table. MML Advisers may in its absolute discretion modify the selection of Underlying Funds at any time and from time to time, and may invest the Funds' assets in additional or different Underlying Funds, including Funds that may be created in

the future. Information regarding the Funds' actual allocations to Underlying Funds is available in the Funds' shareholder reports and at https://www.massmutual.com/funds from time to time. A brief description of the Underlying Funds is provided in the SAI in the section titled "Appendix D — Description of Underlying Funds." Appendix D lists the Underlying Funds by sub-asset class. Each of the MassMutual RetireSMART by JPMorgan Funds may invest up to the full amount of a sub-asset class allocation in any one or more of the Underlying Funds listed on Appendix D for that sub-asset class. More detailed information about each Underlying Fund is available in each Underlying Fund's prospectus.

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| | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| **Investment Option**  | **In <br>Retirement <br>Fund**  | **2020 <br>Fund**  | **2025 <br>Fund**  | **2030 <br>Fund**  | **2035 <br>Fund**  | **2040 <br>Fund**  | **2045 <br>Fund**  | **2050 <br>Fund**  | **2055 <br>Fund**  | **2060 <br>Fund**  | **2065 <br>Fund**  |
|  MassMutual Equity Opportunities Fund  | 2.87% | 2.88% | 3.71% | 4.71% | 3.52% | 3.97% | 5.93% | 6.06% | 6.06% | 5.96% | 6.86% |
| MM Equity Asset Fund | 9.06% | 9.05% | 11.70% | 14.83% | 17.76% | 20.08% | 20.19% | 20.46% | 20.47% | 20.58% | 20.00% |
|  MassMutual Blue Chip Growth Fund  | 1.84% | 1.84% | 2.37% | 3.01% | 5.41% | 6.11% | 6.65% | 6.76% | 6.76% | 6.76% | 6.72% |
| MassMutual Overseas Fund | 3.19% | 3.18% | 4.12% | 5.22% | 7.21% | 8.37% | 9.13% | 9.26% | 9.27% | 9.27% | 9.82% |
|  MassMutual International Equity Fund  | 1.77% | 1.78% | 2.27% | 2.91% | 4.37% | 5.06% | 5.50% | 5.60% | 5.60% | 5.62% | 6.14% |
|  Vanguard Developed Markets Index Fund  | 4.05% | 4.05% | 5.20% | 6.63% | 6.18% | 7.17% | 7.83% | 7.92% | 7.91% | 7.88% | 8.59% |
|  JPMorgan Emerging Markets Research Enhanced Equity Fund  | 1.04% | 1.05% | 1.75% | 2.30% | 5.18% | 5.74% | 6.29% | 6.41% | 6.40% | 6.41% | 4.91% |
| MassMutual Core Bond Fund | 20.42% | 20.42% | 19.05% | 15.24% | 4.35% | 2.33% | 1.16% | 0.94% | 0.94% | 0.94% | 0.96% |
|  Vanguard Total Bond Market Index Fund  | 5.14%  | 5.14%  | 4.78%  | 3.83%  | 1.09%  | 0.58%  | 0.29%  | 0.24%  | 0.24%  | 0.23%  | 0.24%  |
|  MassMutual Total Return Bond Fund  | 6.89% | 6.89% | 6.43% | 5.14% | 7.40% | 4.37% | 2.18% | 1.77% | 1.77% | 1.77% | 1.80% |
| MassMutual Strategic Bond Fund  | 6.92% | 6.92% | 6.46% | 5.17% | 7.43% | 4.40% | 2.19% | 1.78% | 1.78% | 1.78% | 1.80% |
|  MassMutual Inflation-Protected and Income Fund  | 7.39% | 7.39% | 3.83% | 0.59% | 0.00% | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00%  | 0.00% |
| MassMutual High Yield Fund | 5.28% | 5.28% | 5.14% | 4.37% | 2.67% | 2.05% | 1.03% | 0.84% | 0.84% | 0.85% | 0.85% |
|  JPMorgan U.S. Government Money Market Fund  | 12.60% | 12.60% | 7.54% | 5.96% | 5.21% | 3.86% | 3.85% | 3.85% | 3.85% | 3.85% | 4.00% |

---

Other Underlying Funds in which the MassMutual RetireSMART by JPMorgan Funds invest as of January 11, 2023, or expect to invest as of February 1, 2023, as applicable, include: MassMutual Fundamental Value Fund, MassMutual Diversified Value Fund, MassMutual Growth Opportunities Fund, JPMorgan Large Cap Value Fund, MassMutual Mid Cap Value Fund, Vanguard Mid-Cap Index Fund, MassMutual Mid Cap Growth Fund, MassMutual Small Cap Value Equity Fund, Vanguard Small-Cap Index Fund,

MassMutual Small Cap Growth Equity Fund, Vanguard Real Estate Index Fund, MassMutual Strategic Emerging Markets Fund, MassMutual Global Floating Rate Fund, and JPMorgan

Emerging Markets Debt Fund.Each MassMutual

RetireSMART by JPMorgan Fund will bear a pro rata share of its Underlying Funds' expenses. Each MassMutual RetireSMART by JPMorgan Fund also bears all of the risks associated with the investment strategies used by its Underlying Funds.

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### Disclosure of Portfolio Holdings
A description of the Funds' policies and procedures with respect to the disclosure of each Fund's portfolio securities is available in the Funds' SAI.

### Additional Information Regarding Principal Risks
A Fund, by itself, generally is not intended to provide a complete investment program. Investment in the Funds is intended to serve as part of a diversified portfolio of investments. An investment in a Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The value of your investment in a Fund changes with the values of the investments in the Fund's portfolio. Many things can affect those values. Factors that may have an important or significant effect on a particular Fund's portfolio as a whole are called "Principal Risks." The Principal Risks of each Fund are identified in the foregoing Fund Summaries and are described in this section. Certain Funds may be more susceptible to some risks than others. Although the Funds strive to reach their stated goals, they cannot offer guaranteed results. The value of your investment in a Fund could go down as well as up. You can lose money by investing in the Funds. Except as otherwise stated, references in this section to "the Funds" or "a Fund" may relate to the Fund, one or more Underlying Funds, or both.

The SAI contains further information about the Funds, their investments, and their related risks.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Allocation Risk
There is no assurance that allocation decisions will result in the desired performance effects. The limited universe of Underlying Funds and the requirement that a significant percentage of a MassMutual Target Allocation Fund's or MassMutual RetireSMART by JPMorgan Fund's assets be invested in mutual funds advised by MML Advisers, J.P. Morgan, or affiliates of J.P. Morgan, as applicable, as noted in each Fund's "Principal Investment Strategies" may adversely affect Fund performance.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Bank Loans Risk
Many of the risks associated with bank loans are similar to the risks of investing in below investment grade debt securities, although bank loans are typically (though not always)

senior and secured, while below investment grade debt securities or investments are often subordinated and unsecured. Senior loans are subject to the risk that a court could subordinate a senior loan, which typically holds the most senior position in the issuer's capital structure, to presently existing or future indebtedness or take other action detrimental to the holders of senior loans. Changes in the financial condition of the borrower or economic conditions or other circumstances may reduce the capacity of the borrower to make principal and interest payments on such instruments and may lead to defaults. The value of any collateral securing a bank loan may decline after a Fund invests, and there is a risk that the value of the collateral may not be sufficient to cover the amount owed to the Fund. In addition, collateral securing a loan may be found invalid, may be used to pay other outstanding obligations of the borrower under applicable law, or may be difficult to sell. In the event that a borrower defaults, a Fund's access to the collateral may be limited by bankruptcy and other insolvency laws. There is also the risk that the collateral may be difficult to liquidate, or that a majority of the collateral may be illiquid. In addition, some loans may be unsecured. Unsecured loans generally present a greater risk of loss to the Fund if the issuer defaults. In some cases, the Fund may rely on a third party to administer its interest in a loan, and so is subject to the risk that the third party will be unwilling or unable to perform its obligations. The Fund may invest in a loan by purchasing an indirect interest in the loan held by a third party. In that case, the Fund will be subject to both the credit risk of the borrower and of the third party, and the Fund may be unable to realize some or all of the value of its interest in the loan in the event of the insolvency of the third party. The settlement time for certain loans is longer than the settlement time for many other types of investments, and the Fund may not receive the payment for a loan sold by it until well after the sale; that cash would be unavailable for payment of redemption proceeds or for reinvestment. Interests in some bank loans may not be readily marketable and may be subject to restrictions on resale. In some cases, negotiations involved in disposing of indebtedness may require weeks to complete. Consequently, some indebtedness may be difficult or impossible to dispose of

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readily at what the Fund believes to be a fair price. Some bank loans may be illiquid, and bank loans generally tend to be less liquid than many other debt securities. The lack of a liquid secondary market may make it more difficult for the Fund to assign a value to such instruments for purposes of valuing the Fund's portfolio and calculating its net asset value ("NAV"). Some loans may not be considered "securities" for certain purposes under the federal securities laws, and purchasers, such as the Fund, therefore may not be entitled to rely on the anti-fraud protections of the federal securities laws.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Below Investment Grade Debt Securities Risk
Below investment grade debt securities, which are also known as "junk" or "high yield" bonds, and comparable unrated securities in which a Fund may invest, have speculative characteristics, and changes in economic conditions, the financial condition of the issuer, and/or an unanticipated rise in interest rates or other circumstances are more likely to lead to a weakened capacity to make principal and interest payment than in the case of higher grade securities. Below investment grade debt securities involve greater volatility of price and yield and greater risk of loss of principal and interest than do higher quality securities. In the past, economic downturns or increases in interest rates have, under certain circumstances, resulted in a higher incidence of default by the issuers of these instruments and are likely to do so in the future, especially in the case of highly leveraged issuers. The prices for these instruments may be affected by legislative and regulatory developments. Some below investment grade debt securities are issued in connection with management buy-outs and other highly leveraged transactions, and may entail substantial risk of delays in payments of principal or interest or of defaults. The inability (or perceived inability) of issuers to make timely payment of interest and principal would likely make the values of securities held by the Fund more volatile and could limit the Fund's ability to sell its securities at prices approximating the values the Fund has placed on such securities. In the absence of a liquid trading market for securities held by it, a Fund at times may be unable to establish the fair value of such securities. To the extent a Fund invests in securities in the lower rating categories, the

achievement of the Fund's goals is more dependent on the Fund investment adviser's or subadviser's investment analysis than would be the case if the Fund were investing in securities in the higher rating categories. Securities that are rated CCC or below by Standard & Poor's or Caa or below by Moody's Investors Service, Inc. are generally regarded by the rating agencies as having extremely poor prospects of ever attaining any real investment standing.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Cash Position Risk
A Fund may hold a significant portion of its assets in cash or cash equivalents at the sole discretion of the Fund's investment adviser or subadviser, based on such factors as it may consider appropriate under the circumstances. The portion of a Fund's assets invested in cash and cash equivalents may at times exceed 25% of the Fund's net assets. To the extent a Fund holds a significant portion of its assets in cash or cash equivalents, its investments returns may be adversely affected and the Fund may not achieve its investment objective.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; China Investment Risk
Investments in China (including Chinese companies listed on U.S. and Hong Kong exchanges), Hong Kong, and Taiwan, involve certain risks and considerations not typically associated with investments in U.S. companies, including, among others, greater government control over the economy, political and legal uncertainty, currency fluctuations or blockages, the risk that the Chinese government may decide not to continue to support economic reform programs, the risk of nationalization or expropriation of assets, more frequent trading suspensions and government interventions, limits on the use of brokers and on foreign ownership, higher dependence on exports and international trade, potential for increased trade tariffs, embargoes and other trade limitations, and custody risks associated with programs used to access Chinese securities. Additionally, the securities markets of China, Hong Kong, and Taiwan are emerging markets subject to the special risks applicable to emerging market countries. Significant portions of the Chinese securities markets may become rapidly illiquid, as Chinese issuers have the ability to suspend the trading of their equity securities, and have shown a willingness to exercise that option in

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response to market volatility and other events. U.S. sanctions or other investment restrictions could preclude a Fund from investing in certain Chinese issuers or cause a Fund to sell investments at a disadvantageous time.

The Chinese economy is generally considered an emerging and volatile market. Although China has experienced a relatively stable political environment in recent years, there is no guarantee that such stability will be maintained in the future. Political, regulatory, and diplomatic events, such as the U.S.-China "trade war" that intensified in 2018, could have an adverse effect on the Chinese, Taiwanese, or Hong Kong economies and on investments made through China Connect programs. In addition, if China were to exert its authority so as to alter the economic, political, or legal structures or the existing social policy of Hong Kong, investor and business confidence in Hong Kong could be negatively affected, which in turn could negatively affect markets and business performance and have an adverse effect on a Fund's investments. Similarly, although the relationship between China and Taiwan has been improving, there is the potential for future political or economic disturbances between China and Taiwan that may have an adverse impact on the values of investments in either China or Taiwan, or make investments in China and/or Taiwan impractical or impossible.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Cayman Subsidiary Risk
An Underlying Fund may have a wholly-owned subsidiary formed in the Cayman Islands in which it invests (a "Cayman Subsidiary"). Such an Underlying Fund will be indirectly exposed to the risks associated with the Cayman Subsidiary's investments. A Cayman Subsidiary is not registered under the Investment Company Act of 1940, as amended ("1940 Act"), and is not subject to all the investor protections of the 1940 Act. Changes in the laws of the United States and/or the Cayman Islands could result in an increase in expenses and could adversely affect the Underlying Fund. For example, the Cayman Islands does not currently impose any income, corporate, or capital gains tax, estate duty, inheritance tax, gift tax, or withholding tax on a Cayman Subsidiary. If Cayman Islands law changes such that a Cayman Subsidiary must pay Cayman Islands

taxes, the Underlying Fund's shareholders would likely experience decreased investment returns. In addition, changes in law, or interpretations of existing law, including tax law and the regulation of entities that invest in commodity interests, may limit the ability of the Underlying Fund to invest in the Cayman Subsidiary and may limit the ability of the Cayman Subsidiary to invest as actively or as broadly as it might otherwise, and/or increase expenses.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Commodities-Related Investments Risk
Commodity prices (including precious metals) can be extremely volatile and exposure to commodities can cause the NAV of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities or commodity-linked derivative investments may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political and regulatory developments, or factors affecting a particular region, industry, or commodity, such as drought, floods, weather, embargoes, tariffs, and international economic, political, and regulatory developments. The price of a commodity may be affected by demand/supply imbalances in the market for the commodity. Also, a liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or the price at which it is carrying them. A Fund's investments in commodities and commodity-related instruments may bear on or be limited by the Fund's intention or ability to qualify as a "regulated investment company" for U.S. federal income tax purposes. See "Taxation and Distributions" below.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Convertible Securities Risk
Convertible securities are bonds, debentures, notes or other debt securities that may be converted at either a stated price or stated rate into shares of common or preferred stock (or cash or other securities of equivalent value), and so are subject to the risks of investments in both debt securities and equity securities. The price of a convertible security may change in response to changes in price of the

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underlying equity security, the credit quality of the issuer, and interest rates. Due to the conversion feature, convertible debt securities generally yield less than non-convertible securities of similar credit quality and maturity. The values of convertible securities may be interest-rate sensitive and tend to decline as interest rates rise and to rise when interest rates fall. A Fund may invest at times in securities that have a mandatory conversion feature, pursuant to which the securities convert automatically into stock at a specified date and conversion ratio, or that are convertible at the option of the issuer. When conversion is not at the option of the holder, a Fund may be required to convert the security into the underlying stock even at times when the value of the underlying common stock has declined substantially or it would otherwise be disadvantageous to do so.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Credit Risk
Credit risk is the risk that an issuer, guarantor, or liquidity provider of a fixed income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed income security held by the Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when the Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured. The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment grade are considered to have speculative characteristics. In addition, below investment grade debt securities (i.e., "junk" or "high yield" bonds) involve greater credit risk, are more volatile, involve greater risk of price declines and may be more susceptible to economic downturn than investment grade

securities. If a security held by the Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the investment adviser or subadviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages may affect the values of those securities.

The Fund may also be exposed to the credit risk of its counterparty to repurchase agreements, reverse repurchase agreements, swap transactions, and other derivatives transactions, and to the counterparty's ability or willingness to perform in accordance with the terms of the transaction. The value of such transactions to the Fund will depend on the willingness and ability of the counterparty to perform its obligations, including among other things the obligation to return collateral or margin to the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances. In the event of a counterparty's (or its affiliate's) insolvency, the possibility exists that a Fund's ability to exercise remedies, such as the termination of transactions, netting of obligations, and realization on collateral, could be stayed or eliminated under special resolution regimes adopted in the United States, the European Union, the United Kingdom, and various other jurisdictions. Among other things, such regimes provide government authorities with broad authority to intervene when a financial institution is experiencing financial difficulty.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Currency Risk
Because foreign securities normally are denominated and traded in foreign currencies, the value of a Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, currency exchange control regulations, intervention (or failure to intervene) by the U.S. or foreign governments in currency markets, foreign withholding taxes, and restrictions or prohibitions on the repatriation of foreign currencies. A Fund may, but will not necessarily, engage in foreign

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currency transactions in order to protect against fluctuations in the values of holdings denominated in or exposed to other currencies, or, for certain Funds, to generate additional returns. Derivatives transactions providing exposure to foreign currencies may create investment leverage. A Fund's investment in foreign currencies may increase the amount of ordinary income recognized by the Fund.

Officials in foreign countries may from time to time take actions in respect of their currencies which could significantly affect the value of a Fund's assets denominated in those currencies or the liquidity of such investments. For example, a foreign government may unilaterally devalue its currency against other currencies, which would typically have the effect of reducing the U.S. dollar value of investments denominated in that currency. A foreign government may also limit the convertibility or repatriation of its currency or assets denominated in its currency, which would adversely affect the U.S. dollar value and liquidity of investments denominated in that currency. In addition, although at times most of a Fund's income may be received or realized in foreign currencies, the Fund will be required to compute and distribute its income in U.S. dollars. As a result, if the exchange rate for any such currency declines after the Fund's income has been earned and translated into U.S. dollars but before payment to shareholders, the Fund could be required to sell portfolio investments to make such distributions. Similarly, if a Fund incurs an expense in a foreign currency and the exchange rate changes adversely to the Fund before the expense is paid, the Fund would have to convert a greater amount of U.S. dollars to pay for the expense at that time than it would have had to convert at the time the Fund incurred the expense. Investments in foreign currencies themselves (directly or through derivatives transactions) may be highly volatile and may create investment leverage.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Cyber Security and Technology Risk
The Funds and their service providers (including the Funds' investment adviser, subadvisers, custodian, and transfer agent) are subject to operational and information security risks, including those resulting from cyber-attacks and other technological issues. Technological issues or failures, or interference or attacks by "hackers" or others, may have

the effect of disabling or hindering the Funds' operations or the operations of a service provider to the Funds. There are inherent limitations in business continuity plans and technology systems designed to prevent cyber-attacks and avoid operational incidents, including the possibility that certain risks have not been identified. The Funds' investment adviser does not control the cyber security plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Funds' investment adviser or the Funds, each of whom could be negatively impacted as a result. Similar risks also are present for issuers of securities in which the Funds invest, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Defaulted and Distressed Securities Risk
Defaulted securities risk refers to the uncertainty of repayment of defaulted securities and obligations of distressed issuers. Because the issuer of such securities is in default and is likely to be in distressed financial condition, repayment of defaulted securities and obligations of distressed issuers (including insolvent issuers or issuers in payment or covenant default, in workout or restructuring, or in bankruptcy or insolvency proceedings) is subject to significant uncertainties. The market will likely be less liquid for distressed or defaulted securities than for other types of securities. Reduced liquidity can affect the valuations of distressed or defaulted securities, make their valuation and sale more difficult, and result in greater volatility. Insolvency laws and practices in foreign countries are different than those in the U.S. and the effect of these laws and practices cannot be predicted with certainty. Investments in defaulted securities and obligations of distressed issuers are considered speculative. To the extent a Fund is invested in distressed securities, its ability to achieve current income for its shareholders may be diminished.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Derivatives Risk
Derivatives are financial contracts whose values depend upon, or are derived from, the value of an underlying asset, reference rate, or index. Derivatives may relate to stocks, bonds, interest rates, currencies, credit

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exposures, currency exchange rates, commodities, related indexes, or other assets. The use of derivative instruments may involve risks different from, or greater than, the risks associated with investing directly in securities and other more traditional investments. Derivatives can be highly volatile and are subject to a number of potential risks described in this Prospectus, including market risk, credit risk, management risk, liquidity risk, and leveraging risk. Derivative products are highly specialized instruments that may require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument or index but also of the derivative itself, often without the benefit of observing the performance of the derivative under all possible market conditions. (For example, successful use of a credit default swap may require, among other things, an understanding of both the credit of the company to which it relates and of the way the swap is likely to respond to changes in various market conditions and to factors specifically affecting the company.) The use of derivatives involves the risk that a loss may be sustained as a result of the failure of another party to the contract (typically referred to as a "counterparty") to make required payments or otherwise to comply with the contract's terms. Derivative transactions can create investment leverage. Losses from derivatives can be substantially greater than the derivatives' original cost and can sometimes be unlimited. Since the values of derivatives are calculated and derived from the values of other assets, reference rates, or indexes, there is greater risk that derivatives will be improperly valued. Derivatives also involve the risk that changes in the value of a derivative may not correlate perfectly with changes in the value of its underlying asset, rate, or index, and the risk that a derivative transaction may not have the effect or benefit the Fund's investment adviser or subadviser anticipated. Also, suitable derivative transactions may not be available in all circumstances, and there can be no assurance that a Fund will engage in these transactions when that would be beneficial. A liquid secondary market may not always exist for a Fund's derivative positions at any time. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case

with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous price or at all. Although the use of derivatives is intended to enhance a Fund's performance, it may instead reduce returns and increase volatility.

Recent U.S. and non-U.S. legislative and regulatory reforms, including those related to the Dodd-Frank Wall Street Reform and Consumer Protection Act, have resulted in, and may in the future result in, new regulation of derivative instruments and the Funds' use of such instruments. Such regulations can, among other things, restrict a Fund's ability to engage in derivative transactions (for example, by making certain types of derivative instruments or transactions no longer available to a Fund), establish additional margin requirements and/or increase the costs of derivatives transactions, and a Fund may as a result be unable to execute its investment strategies in a manner its investment adviser or subadviser might otherwise choose. Counterparty risk with respect to derivatives has been and may continue to be affected by rules and regulations concerning the derivatives market. Some derivatives transactions are centrally cleared, and a party to a cleared derivatives transaction is subject to the credit risk of the clearing house and the clearing member through which it holds the position. Credit risk of market participants with respect to derivatives that are centrally cleared is concentrated in a few clearing houses and clearing members, and it is not clear how an insolvency proceeding of a clearing house or clearing member would be conducted, what effect the insolvency proceeding would have on any recovery by a Fund, and what impact an insolvency of a clearing house or clearing member would have on the financial system more generally.

*•* *Futures Contract Risk.* A Fund may enter into futures contracts, in which the Fund agrees to buy or sell certain financial instruments or index units or other assets on a specified future date at a specified price or rate. A Fund may also enter into contracts to deliver in the future an amount of one currency in return for an amount of another currency. If a Fund's investment adviser or subadviser misjudges the direction of interest rates, markets, or foreign exchange rates, a Fund's overall performance

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could suffer. The risk of loss could be far greater than the investment made because a futures contract requires only a small deposit to take a large position. A small change in a futures contract could have a substantial impact on a Fund, favorable or unfavorable. An investor could also suffer losses if it is unable to close out a futures contract because of an illiquid market. Futures are subject to the creditworthiness of the futures commission merchants or brokers and clearing organizations involved in the transactions. In the event of the insolvency of its futures commission merchant or broker, a Fund may be delayed or prevented from recovering some or all of the margin it has deposited with the merchant or broker, or any increase in the value of its futures positions held through that merchant or broker.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Dollar Roll and Reverse Repurchase Agreement Transaction Risk
In a dollar roll transaction, a Fund sells mortgage-backed securities for delivery to the buyer in the current month and simultaneously contracts to purchase similar securities on a specified future date from the same party. In a reverse repurchase agreement transaction, a Fund sells securities to a bank or securities dealer and agrees to repurchase them at an agreed time and price; a reverse repurchase agreement is similar to a secured borrowing by a Fund. Both types of transactions generally create leverage. It may be difficult or impossible for a Fund to exercise its rights under a dollar roll transaction or reverse repurchase agreement in the event of the insolvency or bankruptcy of the counterparty, and the Fund may not be able to purchase the securities or other assets subject to the transaction and may be required to return any collateral it holds.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Emerging Markets Risk
Investing in emerging market securities poses risks different from, and/or greater than, risks of investing in domestic securities or in the securities of foreign, developed countries. These risks may include, for example, smaller market-capitalizations of securities markets; significant price volatility; illiquidity; limits on foreign investment; and possible limits on repatriation of investment income and capital. Future economic or political events or crises could lead to price controls, forced mergers,

expropriation or confiscatory taxation, seizure, nationalization, or the creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in those currencies by a Fund. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries. Although many of the emerging market securities in which a Fund may invest are traded on securities exchanges, they may trade in limited volume, and the exchanges may not provide all of the conveniences or protections provided by securities exchanges in more developed markets.

Additional risks of emerging market securities may include greater social, economic, and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; greater custody and operational risks; unavailability of currency hedging techniques; less stringent investor protection and disclosure standards; less reliable settlement practices; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability or unreliability of material information about issuers or instruments; less developed legal, regulatory, and accounting systems; and greater environmental risk. Many emerging market countries are highly reliant on international trade and exports, including the export of commodities. Their economies may be significantly impacted by fluctuations in commodity prices and the global demand for certain commodities. In addition, pandemics and outbreaks of contagious diseases may exacerbate pre-existing problems in emerging market countries with less established health care systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement of securities transactions in emerging markets may be subject to risk of loss and may be delayed more often than transactions settled in the United States, in part because a Fund will need to use brokers and counterparties that

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are less well capitalized, and custody and registration of assets in some countries may be unreliable compared to more developed countries. Settlement problems may cause a Fund to miss attractive investment opportunities, hold a portion of its assets in cash pending settlement, or be delayed in disposing of a portfolio security. It may be more difficult to obtain and/or enforce a judgment in a court outside the U.S., and a judgment against a foreign government may be unenforceable.

Frontier markets, a subset of emerging markets, generally have smaller economies and less mature capital markets than emerging markets. As a result, the risks of investing in emerging market countries are magnified in frontier market countries. Frontier markets are more susceptible to having abrupt changes in currency values, less mature markets and settlement practices, and lower trading volumes that could lead to greater price volatility and illiquidity.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Equity Securities Risk
Although stocks may have the potential to outperform other asset classes over the long term, their prices tend to fluctuate more dramatically over the shorter term. These movements may result from factors affecting individual companies, or from broader influences like changes in interest rates, market conditions, or investor confidence, or announcements of economic, political, or financial information.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ESG Considerations Risk
With respect to certain Funds, the ESG considerations assessed as part of the investment process to implement the Fund's investment strategy in pursuit of its investment objective may vary across types of eligible investments and issuers, and not every ESG factor may be identified or evaluated for every investment. The Fund's portfolio will not be solely based on ESG considerations, and therefore the issuers in which the Fund invests may not be considered ESG-focused companies. The incorporation of ESG factors may affect the Fund's exposure to certain issuers or industries and may not work as intended. The incorporation of ESG factors into a Fund's investment process does not mean that every investment or potential investment undergoes an ESG review, and a

Fund's investment adviser or subadviser may not consider ESG factors for every investment the Fund makes, particularly, for example, in cases where ESG-related data for a potential investment is unavailable. The Fund may underperform other funds that do not assess an issuer's ESG factors or that use a different methodology to identify and/or incorporate ESG factors. Information used by the Fund to evaluate such factors may not be readily available, complete or accurate, and may vary across providers and issuers as ESG is not a uniformly defined characteristic. There is no guarantee that the evaluation of ESG considerations will be additive to the Fund's performance.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Fixed Income Securities Risk
The values of debt securities change in response to interest rate changes. In general, as interest rates rise, the value of a debt security is likely to fall. This risk is generally greater for obligations with longer maturities or for debt securities that do not pay current interest (such as zero-coupon securities). Debt securities with variable and floating interest rates can be less sensitive to interest rate changes, although, to the extent a Fund's income is based on short-term interest rates that fluctuate over short periods of time, income received by the Fund may decrease as a result of a decline in interest rates. The value of a debt security also depends on the issuer's actual or perceived credit quality or ability to pay principal and interest when due. The value of a debt security is likely to fall if an issuer or the guarantor of a security is unable or unwilling (or is perceived to be unable or unwilling) to make timely principal and/or interest payments or otherwise to honor its obligations or if the debt security's rating is downgraded by a credit rating agency. The value of a debt security can also decline in response to changes in market, economic, industry, political, regulatory, public health, and other conditions that affect a particular type of debt security or issuer or debt securities generally. Certain events, such as market or economic developments, regulatory or government actions, natural disasters, pandemics, terrorist attacks, war, and other geopolitical events can have a dramatic adverse effect on the debt market and the overall liquidity of the market for fixed income securities.

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

*•* *Extension Risk.* During periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below-market interest rate, increase the security's duration, and reduce the value of the security.

*•* *Prepayment Risk.* Prepayment risk is the risk that principal of a debt obligation will be repaid at a faster rate than anticipated. In such a case, a Fund may lose the benefit of a favorable interest rate for the remainder of the term of the security in question, and may only be able to reinvest the amount of the prepayment at a less favorable rate.

*•* *Interest Rate Risk.* The values of bonds and other debt instruments usually rise and fall in response to changes in interest rates. The values of debt instruments generally increase in response to declines in interest rates and decrease in response to rises in interest rates. Interest rates can also change in response to the supply and demand for credit, government and/or central bank monetary policy and action, inflation rates, and other factors. Interest rate risk is generally greater for fixed-rate instruments than floating-rate instruments and for investments with longer durations or maturities. Some investments give the issuer the option to call or redeem an investment before its maturity date. If an issuer calls or redeems an investment during a time of declining interest rates, a Fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. Negative or very low interest rates could magnify the risks associated with changes in interest rates. In general, changing interest rates, including rates that fall below zero, could have unpredictable effects on markets and may expose fixed income and related markets to heightened volatility.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Foreign Investment Risk
Investments in securities of foreign issuers, securities of companies with significant foreign exposure, and foreign currencies can involve additional risks relating to market, industry, political, regulatory, public health, and other conditions. Political, social, diplomatic, and economic developments, U.S. and foreign government action, or threat thereof, such as the imposition of currency or capital

blockages, controls, or tariffs, economic and trade sanctions or embargoes, security trading suspensions, entering or exiting trade or other intergovernmental agreements, or the expropriation or nationalization of assets in a particular country, can cause dramatic declines in certain or all securities with exposure to that country and other countries. Economic or other sanctions imposed on a foreign country or issuer by the U.S., or on the U.S. by a foreign country, could impair a Fund's ability to buy, sell, hold, receive, deliver, or otherwise transact in certain securities. In the event of nationalization, expropriation, confiscation, or other government action, intervention, or restriction, a Fund could lose its entire investment in a particular foreign issuer or country. There may be quotas or other limits on the ability of a Fund (or clients of a Fund's investment adviser or subadviser) to invest or maintain investments in securities of issuers in certain countries. Enforcing legal rights can be more difficult, costly, and limited in certain foreign countries and with respect to certain types of investments, and can be particularly difficult against foreign governments. Because non-U.S. securities are normally denominated and traded in currencies other than the U.S. dollar, the value of a Fund's assets may be affected favorably or unfavorably by changes in currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies.

Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. company than about a U.S. company, and many non-U.S. companies are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. companies are less liquid and at times more volatile than securities of comparable U.S. companies. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the United States. In addition, foreign markets can perform differently from U.S. markets and can react differently to market, economic, industry, political, regulatory, geopolitical, public health, and other conditions than the U.S. market.

The willingness and ability of foreign governmental entities to pay principal and

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interest on government securities depends on various economic factors, including for example the issuer's balance of payments, overall debt level, and cash-flow considerations related to the availability of tax or other revenues to satisfy the issuer's obligations. If a foreign governmental entity defaults on its obligations on the securities, a Fund may have limited recourse available to it. The laws of some foreign countries may limit a Fund's ability to invest in securities of certain issuers located in those countries. Special tax considerations apply to a Fund's investments in foreign securities. A Fund's investments in foreign securities or foreign currencies may increase or accelerate the Fund's recognition of ordinary income and may affect the amount, timing, or character of the Fund's distributions.

A Fund may invest in foreign securities known as depositary receipts, in the form of American Depositary Receipts ("ADRs"), European Depositary Receipts ("EDRs"), Global Depositary Receipts ("GDRs"), or other similar securities. An ADR is a U.S. dollar-denominated security issued by a U.S. bank or trust company that represents, and may be converted into, a foreign security. An EDR or a GDR is generally similar but is issued by a non-U.S. bank. Depositary receipts are subject to the same risks as direct investment in foreign securities. Depositary receipts may not necessarily be denominated in the same currency as the underlying securities into which they may be converted, and changes in currency exchange rates may affect the value of an ADR investment in ways different from direct investments in foreign securities. Funds may invest in both sponsored and unsponsored depositary receipts. Unsponsored depositary receipts are organized independently and without the cooperation of the issuer of the underlying securities. As a result, available information concerning the issuers may not be as current for unsponsored depositary receipts and the prices of unsponsored depositary receipts may be more volatile than if such instruments were sponsored by the issuer. In addition, the underlying issuers of certain depositary receipts, particularly unsponsored or unregistered depositary receipts, are under no obligation to distribute shareholder communications to the holders of such receipts or to pass through to them any voting rights with respect to the deposited securities. A Fund

may therefore receive less timely information or have less control than if it invested directly in the foreign issuer. An investment in an ADR is subject to the credit risk of the issuer of the ADR.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Frequent Trading/Portfolio Turnover Risk
The length of time a Fund has held a particular security is not generally a consideration in investment decisions. The investment policies of a Fund may lead to frequent changes in the Fund's investments, particularly in periods of volatile market movements, in order to take advantage of what the Fund's investment adviser or subadviser believes to be temporary investment opportunities. A change in the securities held by a Fund is known as "portfolio turnover." Portfolio turnover generally involves some expense to a Fund, including brokerage commissions, bid-asked spreads, dealer mark-ups, and other transaction costs on the sale of securities and reinvestments in other securities, and may result in the realization of taxable capital gains (including short-term gains, which are generally treated as ordinary income when distributed to shareholders). The trading costs and tax effects associated with portfolio turnover may adversely affect a Fund's performance. Consult your tax adviser regarding the effect of a Fund's portfolio turnover rate on your investments.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Geographic Focus Risk
When a Fund invests a relatively large percentage of its assets in issuers located in a single country, a small number of countries, or a particular geographic region, the Fund's performance could be closely tied to the market, currency, economic, political, or regulatory conditions and developments in those countries or that region, and could be more volatile than the performance of more geographically diversified funds.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Growth Company Risk
Growth company securities tend to be more volatile in terms of price swings and trading volume than many other types of equity securities. Growth companies, especially technology related companies, have seen dramatic rises and falls in stock valuations. Funds that invest in growth companies are subject to the risk that the market may deem these companies' stock prices over-valued,

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which could cause steep and/or volatile price swings. Also, since investors buy these stocks because of their expected superior earnings growth, earnings disappointments often result in sharp price declines.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Hedging Risk
There can be no assurance that a Fund's hedging transactions will be effective. If a Fund takes a short position in a particular currency, security, or bond market, it will lose money if the currency, security, or bond market appreciates in value, or an expected credit event fails to occur. Any efforts at buying or selling currencies could result in significant losses for the Fund. Further, foreign currency transactions that are intended to hedge the currency risk associated with investing in foreign securities and minimize the risk of loss that would result from a decline in the value of the hedged currency may also limit any potential gain that might result should the value of such currency increase.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Index Funds Risk
Certain Underlying Funds may attempt to track the performance of a specified index. Therefore, securities may be purchased, retained, and sold by the Underlying Fund at times when an actively managed fund would not do so. The structure and composition of the index will affect the performance, volatility, and risk of the index and, consequently, the performance, volatility, and risk of the Underlying Fund. While the investment adviser or subadviser seeks to track the performance of the index (i.e., achieve a high degree of correlation with the index), the Underlying Fund's return may not match the return of the index. The Underlying Fund incurs a number of operating expenses not applicable to the index, and may incur costs in buying and selling securities. In addition, the Underlying Fund may not be fully invested at times, generally as a result of cash flows into or out of the Underlying Fund or reserves of cash held by the Underlying Fund to meet redemptions.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Inflation Risk
The value of assets or income from a Fund's investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of a Fund's assets can decline as can the value of the Fund's

distributions. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and a Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors. The market prices of debt securities generally fall as inflation increases because the purchasing power of the future income and repaid principal is expected to be worth less when received by the Fund. Debt securities that pay a fixed rather than variable interest rate are especially vulnerable to inflation risk because variable-rate debt securities may be able to participate, over the long term, in rising interest rates which have historically accompanied long-term inflationary trends.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Inflation-Linked Securities Risk
Inflation-linked securities are typically fixed income securities whose principal values are periodically adjusted according to a measure of inflation. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that such policies will change), and a Fund's investments may not keep pace with inflation, which may result in losses to the Fund's investors. If the index measuring inflation falls, the principal value of an inflation-linked security will be adjusted downward, and consequently the interest payable on the security (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original principal of the security upon maturity (as adjusted for inflation) is guaranteed in the case of U.S. Treasury inflation-linked securities. For securities that do not provide a similar guarantee, the adjusted principal value of the security repaid at maturity may be less than the original principal.

Alternatively, the interest rates payable on certain inflation-linked securities may be adjusted according to a measure of inflation. As a result, the principal values of such securities do not adjust according to the rate of inflation, although the interest payable on such securities may decline during times of falling inflation.

The values of inflation-linked securities are expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest

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rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-linked securities. Inflation-linked securities may cause a potential cash flow mismatch to investors, because an increase in the principal amount of an inflation-linked security will be treated as interest income currently subject to tax at ordinary income rates even though investors will not receive repayment of principal until maturity. If a Fund invests in such securities, it will be required to distribute such interest income in order to qualify for treatment as a regulated investment company and eliminate the Fund-level tax, without a corresponding receipt of cash, and therefore may be required to dispose of portfolio securities at a time when it may not be advantageous to do so in order to make such distributions.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Large Company Risk
Large-capitalization stocks as a group could fall out of favor with the market, causing a Fund's investments in large-capitalization stocks to underperform investments that focus on small- or medium-capitalization stocks. Larger, more established companies may be slow to respond to challenges, including changes to technology or consumer tastes, and may grow more slowly than smaller companies, especially during market cycles corresponding to periods of economic expansion. Market capitalizations of companies change over time.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; LIBOR Risk
Certain instruments in which a Fund may invest rely in some fashion upon the London-Interbank Offered Rate ("LIBOR"). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the head of the United Kingdom's Financial Conduct Authority announced a desire to phase out the use of LIBOR by the end of 2021. The administrator of LIBOR ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of remaining U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators

have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for transition away from LIBOR, but there are obstacles to converting certain instruments to new reference rates. Markets are developing but questions around liquidity in these rates and how to appropriately adjust these rates to mitigate any economic value transfer at the time of transition remain a significant concern. It is difficult to predict the full impact of the transition away from LIBOR on a Fund. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include "fall back" provisions addressing the transition from LIBOR. In addition, uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by a Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Fund.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Liquidity Risk
Liquidity risk is the risk that particular investments may be difficult to sell or terminate at approximately the price at which the Fund is carrying the investments. The ability of a Fund to dispose of illiquid positions at advantageous prices may be greatly limited, and a Fund may have to continue to hold such positions during periods when the investment adviser or subadviser otherwise would have sold them. Some securities held by a Fund may be restricted as to resale, may trade in the over-the-counter ("OTC") market, or may not have an active trading market due to adverse market, economic, industry, political, regulatory, geopolitical, public health, or other conditions. In addition, a Fund, by itself or together with other accounts managed by the investment adviser or subadviser, may hold a position in a security that is large relative to the typical trading volume for that security, which can make it difficult for the Fund to dispose of the position at an advantageous time or price.

Market values for illiquid securities may not be readily available, and there can be no assurance that any fair value assigned to an illiquid security at any time will accurately

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reflect the price a Fund might receive upon the sale of that security. It is possible that, during periods of extreme market volatility or unusually high and unanticipated levels of redemptions or in the case of a liquidation of a Fund, a Fund may be forced to sell large amounts of securities or terminate outstanding transactions at a price or time that is not advantageous in order to meet redemptions or other cash needs or to pay liquidation proceeds. In such a case, the sale proceeds received by a Fund may be substantially less than if the Fund had been able to sell the securities or terminate the transactions in more orderly transactions, and the sale price may be substantially lower than the price previously used by the Fund to value the securities for purposes of determining the Fund's NAV. To the extent a Fund holds illiquid securities, it may be more likely to pay redemption proceeds in kind.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Management Risk
Each Fund is subject to management risk because it relies on the investment adviser's and/or subadviser's investment analysis and its selection of investments to achieve its investment objective. A Fund's investment adviser or subadviser manages the Fund based on its assessment of economic, financial, and market factors and its investment judgment. The investment adviser or subadviser may fail to ascertain properly the appropriate mix of securities for any particular economic cycle. A Fund's investment adviser or subadviser applies its investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that they will produce the intended result. Management risk includes the risk that poor security selection will cause a Fund to underperform relative to other funds with similar investment objectives, or that the timing of movements from one type of security to another could have a negative effect on the overall investment performance of the Fund. There can be no assurance that there will be a liquid market for instruments held by the Fund at any time.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Market Risk
The values of a Fund's portfolio securities may decline, at times sharply and unpredictably, as a result of unfavorable broad market developments, which may affect securities markets generally or particular industries,

sectors, or issuers. The values of a Fund's investments may decline as a result of a number of such factors, including actual or perceived changes in general economic and market conditions, industry, political, regulatory, geopolitical, public health, and other developments, including the imposition of tariffs or other protectionist actions, changes in interest rates, currency rates, or other rates of exchange, and changes in economic and competitive industry conditions. Likewise, terrorism, war, natural and environmental disasters, and epidemics or pandemics may be highly disruptive to economies and markets. For example, the global pandemic outbreak of the novel coronavirus known as COVID-19 and efforts to contain its spread have produced, and will likely continue to produce, substantial market volatility, severe market dislocations and liquidity constraints in many markets, exchange trading suspensions and closures, higher default rates, and global business disruption, and they may result in future significant adverse effects. Such factors, and the effects of other infectious illness outbreaks, epidemics, or pandemics, may have a significant adverse effect on a Fund's performance and have the potential to impair the ability of a Fund's investment adviser, subadviser, or other service providers to serve the Fund and could lead to disruptions that negatively impact the Fund. Different parts of the market and different types of securities can react differently to these conditions. The possibility that security prices in general will decline over short or even extended periods subjects a Fund to unpredictable declines in the value of its shares, as well as potentially extended periods of poor performance. In addition, the increasing popularity of passive index-based investing may have the potential to increase security price correlations and volatility. As passive strategies generally buy or sell securities based simply on inclusion and representation in an index, securities' prices will have an increasing tendency to rise or fall based on whether money is flowing into or out of passive strategies rather than based on an analysis of the prospects and valuation of individual securities. This may result in increased market volatility as more money is invested through passive strategies.

Federal, state, and other governments, their regulatory agencies, or self-regulatory organizations may take actions that affect the regulation of the securities in which a Fund

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invests or the issuers of such securities in ways that are unforeseeable. The uncertainty surrounding the sovereign debt of a significant number of European Union countries, as well as the status of the Euro, the European Monetary Union, and the European Union itself, has disrupted and may continue to disrupt markets in the U.S. and around the world. The risks associated with investments in Europe may be heightened due to the United Kingdom's exit from the European Union on January 31, 2020. An agreement between the United Kingdom and the European Union governing their future trade relationship became effective on January 1, 2021. Significant uncertainty remains in the market regarding the ramifications of that development and the arrangements that will apply to the United Kingdom's relationship with the European Union and other countries following its withdrawal; the range and potential implications of possible political, regulatory, economic, and market outcomes are difficult to predict. There is the potential for decreased trade, capital outflows from the United Kingdom, devaluation of the pound sterling, decreased business and consumer spending and decreased foreign investment in the United Kingdom, and negative effects on the value of a Fund's investments and/or on a Fund's ability to enter into certain transactions or value certain investments. If one or more additional countries leave the European Union, or the European Union partially or completely dissolves, the world's economies and securities markets may be significantly disrupted and adversely affected. Legislation or regulation also may change the way in which a Fund, the investment adviser, or subadviser is regulated. Such legislation, regulation, or other government action could limit or preclude a Fund's ability to achieve its investment objective and affect the Fund's performance.

In addition, military action by Russia in Ukraine could adversely affect global energy and financial markets, and therefore could affect the value of a Fund's investments, including beyond the Fund's direct exposure to Russian issuers or nearby geographic regions. The extent and duration of the military action, sanctions, and resulting market disruptions are impossible to predict and could be substantial.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Maturity Date and Redemption Risk
For each of the MassMutual RetireSMART by JPMorgan Funds with a specified target retirement year in its name, even if all shareholders limit their withdrawals from the Fund to the sample withdrawal amounts provided by J.P. Morgan from time to time, there can be no assurance that the Fund will have sufficient assets to make distributions to shareholders throughout the entire Spending Phase. A Fund's assets will decline over time and reach zero on or before the maturity date. If a Fund's assets decline more rapidly than anticipated, the Fund may have insufficient assets to make payments to shareholders at previously anticipated levels throughout the entire Spending Phase. As a Fund's assets decline and approach zero, the Fund might be liquidated, if for example MML Advisers were to determine that the Fund can no longer be managed consistent with its investment objective. In addition, as assets in a Fund decline, Fund expenses will be spread over a smaller asset base, potentially causing an increase in the Fund's expense ratio. In order to accommodate investors redeeming shares, a Fund may sell securities at times when it would not otherwise do so, which may adversely affect the Fund's performance. These transactions may result in higher portfolio turnover, accelerate the realization of taxable income if sales of securities result in capital gains or other income, and increase transaction costs. To the extent that such transactions result in short-term capital gains, such gains will generally be taxed at the ordinary income tax rate. It is possible for a Fund to suffer substantial investment losses and simultaneously experience additional asset reductions as a result of shareholders redeeming shares.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Mortgage- and Asset-Backed Securities Risk
Investments in mortgage-related and other asset-backed securities are subject to the risk of severe credit downgrades, illiquidity and defaults to a greater extent than many other types of fixed income investments. Mortgage-backed securities, including collateralized mortgage obligations and certain stripped mortgage-backed securities, represent a participation in, or are secured by, mortgage loans. Asset-backed securities are generally structured like mortgage-backed securities, but instead of mortgage loans or interests in

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mortgage loans, the underlying assets may include such items as motor vehicle installment sale or installment loan contracts, leases of various types of real and personal property, receivables from credit card agreements, and student loan payments. Asset-backed securities also may be backed by pools of corporate or sovereign bonds, loans made to corporations, or a combination of these bonds and loans, commonly referred to as "collateralized debt obligations," including collateralized bond obligations ("CBOs") and collateralized loan obligations ("CLOs"). The assets backing collateralized debt obligations may consist in part or entirely of high risk, below investment grade debt obligations (or comparable unrated obligations). In the case of CBOs and certain other collateralized debt obligations, those may include, by way of example, high yield debt, residential privately issued mortgage-related securities, commercial privately issued mortgage-related securities, trust preferred securities, and emerging market debt. In the case of CLOs, they may include, among other things, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, any or all of which may be rated below investment grade or may be comparable unrated obligations.

Traditional debt investments typically pay a fixed rate of interest until maturity, when the entire principal amount is due. By contrast, payments on mortgage-backed and many asset-backed investments typically include both interest and partial payment of principal. Principal may also be prepaid voluntarily, or as a result of refinancing or foreclosure. The Fund may have to invest the proceeds from prepaid investments in other investments with less attractive terms and yields. As a result, these securities may have less potential for capital appreciation during periods of declining interest rates than other securities of comparable maturities, although they may have a similar risk of decline in market value during periods of rising interest rates. Because the prepayment rate generally declines as interest rates rise, an increase in interest rates will likely increase the duration, and thus the volatility, of mortgage-backed and asset-backed securities. (Duration is a measure of the expected life of a fixed income security that is used to determine the sensitivity of the security's price to changes in interest rates. Unlike the maturity of a fixed income security,

which measures only the time until final payment is due, duration takes into account the time until all payments of interest and principal on a security are expected to be made, including how these payments are affected by prepayments and by changes in interest rates.) Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. In addition to interest rate risk (as described under "Interest Rate Risk"), investments in mortgage-backed securities composed of subprime mortgages and investments in CDOs and CLOs backed by pools of high-risk, below investment grade debt securities may be subject to a higher degree of credit risk, valuation risk, and liquidity risk (as described under "Credit Risk," "Valuation Risk," and "Liquidity Risk"). During periods of deteriorating economic conditions, such as recessions or periods of rising unemployment, delinquencies and losses generally increase, sometimes dramatically, with respect to securitizations involving loans, sales contracts, receivables, and other obligations underlying mortgage-related and other asset-backed securities. Litigation with respect to the representations and warranties given in connection with the issuance of mortgage-backed securities can be an important consideration in investing in such securities, and the outcome of any such litigation could significantly impact the value of the Fund's mortgage-backed investments.

The types of mortgages underlying securities held by the Fund may differ and may be affected differently by market factors. For example, the Fund's investments in residential mortgage-backed securities will likely be affected significantly by factors affecting residential real estate markets and mortgages generally; similarly, investments in commercial mortgage-backed securities will likely be affected significantly by factors affecting commercial real estate markets and mortgages generally.

Some mortgage-backed and asset-backed investments receive only the interest portion ("IOs") or the principal portion ("POs") of payments on the underlying assets. The yields and values of these investments are extremely sensitive to changes in interest rates and in

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the rate of principal payments on the underlying assets. IOs tend to decrease in value if interest rates decline and rates of repayment (including prepayment) on the underlying mortgages or assets increase; it is possible that the Fund may lose the entire amount of its investment in an IO due to a decrease in interest rates. Conversely, POs tend to decrease in value if interest rates rise and rates of repayment decrease. Moreover, the market for IOs and POs may be volatile and limited, which may make them difficult for the Fund to buy or sell. The values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the benefits of the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

The Fund may gain investment exposure to mortgage-backed and asset-backed investments by entering into agreements with financial institutions to buy the investments at a fixed price at a future date. The Fund may or may not take delivery of the investments at the termination date of such an agreement, but will nonetheless be exposed to changes in value of the underlying investments during the term of the agreement. These transactions may create investment leverage.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Preferred Stock Risk
Like other equity securities, preferred stock is subject to the risk that its value may decrease based on actual or perceived changes in the business or financial condition of the issuer. In addition, if interest rates rise, the dividends on preferred stocks may be less attractive, causing the prices of preferred stocks to decline. Preferred stock may have mandatory sinking fund provisions or call/redemption provisions that can negatively affect its value. In addition, in the event of liquidation of a corporation's assets, the rights of preferred stock generally are subordinate to the rights associated with a corporation's debt securities.

Preferred stocks are also subject to additional risks, such as potentially greater volatility and risks related to deferral, non-cumulative dividends, subordination, liquidity, limited voting rights, and special redemption rights.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Quantitative Models Risk
Certain portfolio managers use quantitative models as part of the idea generation process. Quantitative models are based upon many factors that measure individual securities relative to each other. Such models may not produce the intended results and can be adversely affected by errors or imperfections in the factors or the data on which measurements are based, changing sources of market return or market risk, or any technical issues with or errors in the design, construction, implementation, or maintenance of the models.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Real Estate Risk; REIT Risk
Investments in real estate are subject to a number of risks, including losses from casualty, condemnation or natural disasters, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, environmental regulations and other governmental action, regulatory limitations on rents, property taxes, and operating expenses. An investment in a REIT may be subject to risks similar to those associated with direct ownership of real estate, and may be subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for favorable tax treatment under the Code, and to the risk of general declines in stock prices. In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. A "mortgage" REIT that invests most or all of its assets in mortgages will be subject to many of the risks described above in respect of mortgage-backed securities. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. As a shareholder in a REIT a Fund, and indirectly the Fund's shareholders, would bear its ratable share of the REIT's expenses and would at the same time continue to pay its own fees and expenses. Real estate-related investments may entail leverage and may be highly volatile. The

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securities of small real-estate issuers can be more volatile and less liquid than securities of larger issuers and their issuers can have more limited financial resources.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions by Significant Investors
A Fund may be an investment option for investors who may make substantial investments in the Fund. As a result, from time to time, a Fund may experience a relatively large redemption and could be required to liquidate assets at inopportune times or at a loss or depressed value, which could cause the value of your investment to decline. Similarly, large Fund share purchases may adversely affect a Fund's performance to the extent that the Fund is delayed in investing new cash and is required to maintain a larger cash position than it ordinarily would, or if the Fund is unable to invest the cash in portfolio securities that it considers as desirable as the Fund's portfolio securities.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Repurchase Agreement Risk
A Fund may enter into repurchase agreements. These transactions must be fully collateralized, but involve credit risk to a Fund if the other party should default on its obligation and the Fund is delayed or prevented from recovering the collateral, or if the Fund is required to return collateral to a borrower at a time when it may realize a loss on the investment of that collateral.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Risk of Investment in other Funds or Pools
A Fund may invest in other investment companies or pooled vehicles, including closed-end funds, trusts, and exchange-traded funds ("ETFs"), that are advised by the Fund's investment adviser or subadviser, as applicable, their affiliates, or by unaffiliated parties, to the extent permitted by applicable law. As a shareholder in an investment company or other pool, the Fund, and indirectly that Fund's shareholders, bear a ratable share of the investment company's or pool's expenses, including, but not limited to, advisory and administrative fees, and the Fund at the same time continues to pay its own fees and expenses. Investment companies or pools in which the Funds may invest may change their investment objectives or policies without the approval of a Fund, in which case a Fund may be forced to withdraw its investment from the investment company or

pool at a disadvantageous time. Private investment pools in which the Funds may invest are not registered under the 1940 Act, and so will not offer all of the protections provided by the 1940 Act (including, among other things, independent oversight, protections against certain conflicts of interest, and custodial risks). A Fund is exposed indirectly to all of the risks applicable to any other investment company or pool in which it invests, including that the investment company or pool will not perform as expected. Investments in other investment companies or private pools may be illiquid, may be leveraged, and may be highly volatile.

Investing in other investment companies or private investment vehicles sponsored or managed by the investment adviser or subadviser, as applicable, or affiliates of the investment adviser or subadviser, as applicable, involves potential conflicts of interest. For example, the investment adviser or subadviser, as applicable, or their affiliates may receive fees based on the amount of assets invested in such other investment vehicles, which fees may be higher than the fees the investment adviser or subadviser, as applicable, receives for managing the investing Fund. Investment by a Fund in those other vehicles may be beneficial in the management of those other vehicles, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the investment adviser or subadviser, as applicable, will have an incentive to invest a portion of a Fund's assets in investment vehicles sponsored or managed by the investment adviser or subadviser, as applicable, or their affiliates in lieu of investments by the Fund directly in portfolio securities, and will have an incentive to invest in such investment vehicles over non-affiliated investment companies to ensure an appropriate level of revenue to such investment adviser or subadviser, as applicable, or their affiliates. The investment adviser or subadviser, as applicable, will have no obligation to select the least expensive or best performing funds available to serve as an underlying investment vehicle. Similarly, the investment adviser or subadviser, as applicable, will have an incentive to delay or decide against the sale of interests held by the Fund in investment vehicles sponsored or managed by the investment adviser or subadviser, as applicable, or their affiliates.

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ETFs are subject to many of the same risks applicable to investments in mutual funds generally, including that an ETF will not perform as anticipated, that a Fund will bear its proportionate share of the ETF's fees and expenses, and that the ETF will lose money. ETFs are also subject to additional risks, including, among others, the risk that the market price of an ETF's shares may trade above or below its NAV, the risk that an active trading market for an ETF's shares may not develop or be maintained, the risk that trading of an ETF's shares may be halted, and the risk that the ETF's shares may be delisted from the listing exchange. Some ETFs engage in derivatives strategies and use leverage, and as a result their values can be highly volatile. It is possible that an ETF's performance will diverge from the performance of any index or indexes it seeks to replicate. Because shares of ETFs may be actively traded, their values may be affected in unanticipated ways by the effects of supply and demand in the market for shares of ETFs, activities of short sellers, or unusual speculative activity in their shares. Some ETFs may experience periods of reduced liquidity due to restrictions on trading activity or due to a general lack of investor interest in the asset class represented by the ETF. Unlike shares of a mutual fund, which can be bought and redeemed from the issuing fund by all shareholders at a price based on NAV, shares of an ETF may be purchased or redeemed directly from the ETF solely by Authorized Participants ("APs") and only in aggregations of a specified number of shares ("Creation Units"). ETFs may have a limited number of financial institutions that act as APs. To the extent that those APs exit the business, or are unable to or choose not to process creation and/or redemption orders for Creation Units, and no other AP steps forward to create and redeem ETF shares, the ETF's shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Sample Withdrawal Amount Risk
For each of the MassMutual RetireSMART by JPMorgan Funds with a specified target retirement year in its name, the Spending Phase of the Fund is designed for investors in retirement who intend to spend down their holdings in the Fund. There is no guarantee that a Fund will provide sufficient retirement

income during the Spending Phase, or that an investor's account in the Fund will not be exhausted prior to the target maturity year. The sample withdrawal amount for any given year may be zero in order to preserve capital and you may lose money invested in a Fund. You should not rely on the sample withdrawal amount in determining your retirement income needs. Prior to investing in a Fund, you should be aware of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The value of your investment in a Fund will likely decline during the Spending Phase. If you choose to redeem shares in accordance with the sample withdrawal amount (or any other amount) and a Fund outperforms after you have redeemed shares, you will not participate in the appreciation of assets on the amount you redeemed. The long-term risk and return target of a Fund in any given year, including any income and gain from investments earned by the Fund, is not designed to provide an investment return equal to or greater than the sample withdrawal amount for such year.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; J.P. Morgan will seek to manage the overall volatility of a Fund during the Spending Phase, but it may not be successful in doing so, and the Fund's risk profile may be more or less aggressive from year to year. Your risk tolerance may change over time, and J.P. Morgan may change a Fund's long-term risk and return target, including, but not limited to, in response to market events. For example, to the extent that market performance leads a Fund to underperform (outperform) the long term risk and return target for a given year, it may lead to a decrease (increase) in the sample withdrawal amount or an increase (decrease) in the long term risk and return target in subsequent years. It is important that you re-evaluate your investment in a Fund periodically.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount is calculated on the basis of the information considered by J.P. Morgan as of the applicable calculation date. Once a sample withdrawal amount is set for a given year, J.P. Morgan does not expect to modify it during the year. Rather, any changes to the sample withdrawal amount, including changes to account for unexpected factors, including market performance, will be made in the next annual calculation.

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The sample withdrawal amount calculation assumes the reinvestment of distributions in additional shares of a Fund. As a result, if you do not reinvest distributions and you withdraw from a Fund in any year an amount equal to the sample withdrawal amount without adjusting for distributions not reinvested, you will increase the likelihood that the value of your investment in a Fund will be exhausted prior to the target maturity year.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Sector Risk
If a Fund allocates a substantial amount of its assets to one or more particular industries or to particular economic, market, or industry sectors, then economic, business, regulatory, or other developments affecting issuers in those industries or sectors may affect the Fund adversely to a greater extent than if the Fund had invested more broadly. Examples might include investments in the technology, health care, or financial sectors or in one or more industries within those sectors. A substantial investment in one or more such industries or sectors has the potential to increase the volatility of a Fund's portfolio, and may cause the Fund to underperform other mutual funds.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Short Sales Risk
If a Fund sells a security short, it will make money if the security's price goes down (in an amount greater than any transaction costs) and will lose money if the security's price goes up. There is no limit on the amount of money a Fund may lose on a short sale. A Fund may not be able to close out a short sale when it might wish to do so, or may only do so at an unfavorable price. Short sales can involve leverage. When the Fund engages in a short sale, it typically borrows the security sold short. The Fund will ordinarily have to pay a fee or premium to borrow the security and will be obligated to repay to the lender of the security any dividends or interest that accrue on the security during the period of the loan. If the Fund invests the proceeds from short positions in other securities the Fund could lose money both on the short positions and on the securities in which it has invested the short proceeds.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Small and Mid-Cap Company Risk
Small and medium-sized companies may have limited product lines, markets, or financial

resources or they may depend on a few key employees. Such companies may have been recently organized and have little or no track record of success. Also, a Fund's investment adviser or subadviser may not have had an opportunity to evaluate such newer companies' performance in adverse or fluctuating market conditions. Market risk and liquidity risk are particularly pronounced for stocks of small and medium-sized companies. The securities of small and medium-sized companies may trade less frequently and in smaller volume than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and a Fund may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in such securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of small and medium-sized issuers may be illiquid or may be restricted as to resale.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Sovereign Debt Obligations Risk
Investments in debt securities issued by governments or by government agencies and instrumentalities involve the risk that the governmental entities responsible for repayment may be unable or unwilling to pay interest and repay principal when due. A governmental entity's willingness or ability to pay interest and repay principal in a timely manner may be affected by a variety of factors, including its cash flow, the size of its reserves, its access to foreign exchange, the relative size of its debt service burden to its economy as a whole, and political constraints. A governmental entity may default on its obligations or may require renegotiation or rescheduling of debt payments. Any restructuring of a sovereign debt obligation held by the Fund will likely have a significant adverse effect on the value of the obligation. In the event of default of sovereign debt, the Fund may be unable to pursue legal action against the sovereign issuer or to realize on collateral securing the debt. The sovereign debt of many non-U.S. governments, including their sub-divisions and instrumentalities, is rated below investment grade ("junk" or "high yield" bonds). Sovereign debt risk may be greater for debt securities issued or guaranteed

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by emerging and/or frontier market countries. At times, certain emerging and frontier market countries have declared moratoria on the payment of principal and interest on external debt. Certain emerging and frontier market countries have experienced difficulty in servicing their sovereign debt on a timely basis, which has led to defaults and the restructuring of certain indebtedness to the detriment of debtholders.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Stock Connect Risk
A Fund may invest in China A Shares, which are equity securities of companies domiciled in China that are denominated and traded in Renminbi on the Shanghai or Shenzhen Stock Exchanges. A Fund may invest in A Shares listed and traded on the Shanghai Stock Exchange or Shenzhen Stock Exchange through the Stock Connect program. A Fund's investments in Stock Connect A Shares are generally subject to Chinese securities regulations and listing rules, among other restrictions that may affect the Fund's investments and returns, including transfer restrictions, trading suspensions, and daily limits on net purchases, which are subject to change. Such investments are also subject to heightened operational, tax, and settlement risk and the risk of price fluctuations of A Shares during times when Stock Connect is not trading. Stock Connect is a relatively new program. Further developments are likely and there can be no assurance as to the program's continued existence or whether future developments regarding the program may restrict or adversely affect the Fund's investments or returns.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Tactical Allocation Risk
For each of the MassMutual RetireSMART by JPMorgan Funds, J.P. Morgan has discretion to make short- to intermediate-term tactical allocations that increase or decrease the exposure to asset classes and investments. The Fund's tactical allocation strategy may not be successful in adding value, may increase losses to the Fund, and/or may cause the Fund to have a risk profile different than that portrayed in its "Principal Investment Strategies" from time to time.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; U.S. Government Securities Risk
U.S. Government securities include a variety of securities that differ in their interest rates, maturities, and dates of issue. While securities issued or guaranteed by some agencies or

instrumentalities of the U.S. Government (such as the Government National Mortgage Association) are supported by the full faith and credit of the United States, securities issued or guaranteed by certain other agencies or instrumentalities of the U.S. Government (such as Federal Home Loan Banks) are supported only by the right of the issuer to borrow from the U.S. Government. Securities issued or guaranteed by certain other agencies and instrumentalities of the U.S. Government (such as Fannie Mae and Freddie Mac) are not supported by the full faith and credit of the U.S. Government and are supported only by the credit of the issuer itself. There is no assurance that the U.S. Government would provide financial support to its agencies and instrumentalities if not required to do so. For securities not backed by the full faith and credit of the United States, a Fund must look principally to the agency or instrumentality issuing or guaranteeing the securities for repayment and may not be able to assert a claim against the United States if the agency or instrumentality does not meet its commitment. Such securities may involve increased risk of loss of principal and interest compared to government debt securities that are backed by the full faith and credit of the United States. From time to time, uncertainty regarding the status of negotiations in the U.S. Government to increase the statutory debt ceiling could increase the risk that the U.S. Government may default on payments on certain U.S. Government securities, cause the credit rating of the U.S. Government to be downgraded, increase volatility in the stock and bond markets, result in higher interest rates, reduce prices of U.S. Treasury securities, and/or increase the costs of various kinds of debt. If a U.S. Government-sponsored entity is negatively impacted by legislative or regulatory action (or lack thereof), is unable to meet its obligations, or its creditworthiness declines, the performance of each Fund that holds securities of the entity will be adversely impacted. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. Investments in these securities are also subject

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to, among other things, interest rate risk, prepayment risk, extension risk, and the risk that the value of the securities will fluctuate in response to political, market, or economic developments.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Valuation Risk
A portion of a Fund's assets may be valued at fair value pursuant to guidelines that have been approved by the Trustees. A Fund's assets may be valued using prices provided by a pricing service or, alternatively, a broker-dealer or other market intermediary (sometimes just one broker-dealer or other market intermediary) when other reliable pricing sources may not be available. The Fund, or persons acting on its behalf, may determine a fair value of a security based on such other information as may be available to them. There can be no assurance that any fair valuation of an investment held by a Fund will in fact approximate the price at which the Fund might sell the investment at the time. Technological issues or other service disruption issues involving third-party service providers may limit the ability of the Fund to value its investment accurately or timely. To the extent a Fund sells a security at a price lower than the price it has been using to value the security, its NAV will be adversely affected. If a Fund has overvalued securities it holds, you may pay too much for the Fund's shares when you buy into the Fund. If a Fund underestimates the price of its portfolio securities, you may not receive the full market value for your Fund

shares when you sell.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Value Company Risk
A Fund may purchase some equity securities at prices below what the investment adviser or subadviser considers to reflect their actual or potential fundamental values. The Fund bears the risk that the prices of these securities may not increase to reflect what the investment adviser or subadviser believes to be their fundamental value or that the investment adviser or subadviser may have overestimated the securities' fundamental value or that it may take a substantial period of time to realize that value.

• #### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; When-Issued, Delayed Delivery, TBA, and Forward Commitment Transaction Risk
A Fund may purchase securities on a when-issued, delayed delivery, to-be-announced, or forward commitment basis. These transactions involve a commitment by a Fund to purchase securities for a predetermined price or yield, with payments and delivery taking place more than seven days in the future, or after a period longer than the customary settlement period for that type of security. These transactions involve a risk of loss if the value of the securities declines prior to the settlement date. These transactions may create investment leverage. Recently finalized rules of the Financial Industry Regulatory Authority impose mandatory margin requirements for certain types of when-issued, TBA, or forward commitment transactions, with limited exceptions. Such transactions historically have not been required to be collateralized, and mandatory collateralization could increase the cost of such transactions and impose added operational complexity and may increase the credit risk of such transactions to a Fund.

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### Management of the Funds

#### Investment Adviser and Portfolio Managers
**MML Investment Advisers, LLC** ("MML Advisers"), a Delaware limited liability company, located at 1295 State Street, Springfield, Massachusetts 01111-0001, is the Funds' investment adviser and is responsible for providing all necessary investment management and administrative services. MML Advisers, formed in 2013, is a wholly-owned subsidiary of Massachusetts Mutual Life Insurance Company ("MassMutual"). Founded in 1851, MassMutual is a mutual life insurance company that provides a broad range of insurance, money management, retirement, and asset accumulation products and services for individuals and businesses. As of September 30, 2022, MML Advisers had assets under management of approximately $41.9 billion.

The Funds do not pay an investment management fee to MML Advisers.

A discussion regarding the basis for the Trustees approving any investment advisory contract of the Funds is available in the Funds' annual report to shareholders dated September 30, 2022.

Each Fund pays MML Advisers an administrative and shareholder services fee to compensate it for providing general administrative services to the Funds and for providing or causing to be provided ongoing shareholder servicing to direct and indirect investors in the Funds. MML Advisers pays substantially all of the fee to third parties who provide shareholder servicing and investor recordkeeping services. The fee is calculated and paid based on the average daily net assets attributable to each share class of the Fund separately, and is paid at the following annual rates: 0.10% for Class R5 shares; 0.20% for Service Class shares; 0.30% for Administrative Class shares; 0.20% for Class R4 shares; 0.30% for Class A shares; 0.20% for Class R3 shares; and 0.10% for Class Y shares. Class I shares do not pay any administrative and shareholder services fee.

As the investment adviser to the Funds, MML Advisers is responsible for furnishing a continuous investment program for the Funds, determining the Underlying Funds in which the Funds will invest from time to time, and the portions of their assets the Funds will invest in those Underlying Funds. MML Advisers places purchase and redemption orders for shares of the Underlying Funds on behalf of the Funds. These functions are performed by portfolio managers Frederick (Rick) Schulitz, CFA, CAIA and Michael J. Abata, CFA. In addition to his role as portfolio manager, Mr. Schulitz is also Head of Multi-Asset Class Solutions at MML Advisers, which he joined in 2014. Mr. Schulitz is also Head of Multi-Asset Class Solutions at MassMutual, which he joined in 2006. Mr. Abata joined MML Advisers in 2022. Mr. Abata is also a Multi Asset Class Solutions Strategist at MassMutual, which he joined in 2022. Prior to joining MML Advisers and MassMutual, Mr. Abata was a Director of Research and Portfolio Manager for Quantitative Strategies at Invesco.

#### Subadviser and Portfolio Managers
MML Advisers contracts with J.P. Morgan to provide the glide path and tactical allocations for the ***MassMutual RetireSMART by JPMorgan Funds****.* Subject to the oversight of the Trustees, MML Advisers has the ultimate responsibility to oversee J.P. Morgan and recommend its hiring, termination, and replacement. This responsibility includes, but is not limited to, analysis and review of J.P. Morgan's performance, as well as assistance in the identification and vetting of a new or replacement subadviser. In addition, MML Advisers maintains responsibility for a number of other important obligations, including, among other things, board reporting, assistance in the annual advisory contract renewal process, and, in general, the performance of all obligations not delegated to J.P. Morgan. MML Advisers also provides advice and recommendations to the Trustees, and performs such review and oversight functions as the Trustees may reasonably request, as to the continuing appropriateness of the investment objective, strategies, and policies of each Fund, valuations of portfolio securities, and other matters relating generally to the investment program of each Fund.

**J.P. Morgan Investment Management Inc.** ("J.P. Morgan"), located at 383 Madison Avenue, New York, New York 10179, provides the glide path and tactical allocations for the ***MassMutual RetireSMART by JPMorgan Funds***. J.P. Morgan is a wholly-owned subsidiary of JP Morgan Asset Management Holdings Inc., which is a wholly-owned subsidiary of JP Morgan Chase & Co., a bank holding company. As of September 30, 2022, J.P. Morgan and its affiliates had approximately $2.23 trillion in assets under management.

Daniel Oldroyd, CFA, CAIA

is a portfolio manager of each ***MassMutual RetireSMART by JPMorgan Fund****.* Mr. Oldroyd, Managing Director, joined J.P. Morgan in 2000 and is Head of Target Date Strategies.

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Silvia Trillo

is a portfolio manager of each ***MassMutual RetireSMART by JPMorgan Fund****.* Ms. Trillo, Managing Director, joined J.P. Morgan in 2011.

The Funds' SAI provides additional information about each portfolio manager's compensation, other accounts managed by the portfolio managers, and each portfolio manager's ownership of securities in the relevant Fund.

MML Advisers has received exemptive relief from the Securities and Exchange Commission ("SEC") to permit it to change subadvisers or hire new subadvisers for a number of the series of the Trust from time to time without obtaining shareholder approval. (In the absence of that exemptive relief, shareholder approval might otherwise be required.) Several other mutual fund companies have received similar relief. MML Advisers believes having this authority is important, because it allows MML Advisers to remove and replace a subadviser in a quick, efficient, and cost-effective fashion when, for example, the subadviser's performance is inadequate or the subadviser no longer is able to meet a Trust series' investment objective and strategies. Pursuant to the exemptive relief, MML Advisers will provide to a Fund's shareholders, within 90 days of the hiring of a new subadviser, an information statement describing the new subadviser. MML Advisers will not rely on this authority for any Fund unless the Fund's shareholders have approved this arrangement. As of the date of this Prospectus, this exemptive relief is available to each Fund.

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About the Classes of Shares – I, R5, Service, Administrative, R4, A, R3, and Y Shares

#### Choosing a Share Class.
Each Fund (other than the MassMutual 20/80 Allocation Fund, MassMutual 40/60 Allocation Fund, MassMutual 60/40 Allocation Fund, and MassMutual 80/20 Allocation Fund) offers seven classes of shares. The MassMutual 20/80 Allocation Fund, MassMutual 40/60 Allocation Fund, MassMutual 60/40 Allocation Fund, and MassMutual 80/20 Allocation Fund also offer Class Y.

The only differences among the various classes are that (a) each class is subject to different expenses specific to that class, including any expenses under a Rule 12b-1 Plan and administrative and shareholder service expenses; (b) each class has a different class designation; (c) each class has exclusive voting rights with respect to matters solely affecting such class; and (d) each class has different exchange privileges. Not all of the classes of a Fund are available in every state.

Determining which share class is best for you depends on the dollar amount you are investing and the number of years for which you are willing to invest. Based on your personal situation, your financial intermediary can help you decide which class of shares makes the most sense for you. A financial intermediary is entitled to receive compensation for purchases made through the financial intermediary. The Funds, the transfer agent, and MML Distributors, LLC (the "Distributor") do not provide investment advice.

Investors may receive different levels of service in connection with investments in different classes of shares, and intermediaries may receive different levels of compensation in connection with selling different classes of shares. For additional information, call us toll free at 1-888-309-3539 or contact a sales representative or financial intermediary who offers the classes.

#### Fees and Expenses.
Different classes of shares are subject to different fees and expenses. A class's fees and expenses will affect the performance of that class.

• **Administrative and Shareholder Services Fee:** Shares of all classes, *except Class I shares*, are subject to an administrative and shareholder services fee. This fee is described above under "Management of the Funds – Investment Adviser."

• **Servicing or Distribution Fees:** Class R4, Class A, and Class R3 shares are subject to servicing

or distribution fees paid under a Rule 12b-1 Plan. These fees are described below in "Distribution Plan, Shareholder Servicing, and Payments to Intermediaries."

For actual past expenses of Class I, Class R5, Service Class, Administrative Class, Class R4, Class A, and Class R3 shares, see the "Financial Highlights" tables later in this Prospectus.

#### Purchasing Shares.
Different classes of shares are available to different investors and from different sources.

• **Institutional Distribution Channels:** Class I, Class R5, Service Class, and Administrative Class shares are offered primarily to institutional investors through institutional distribution channels. These channels include employer-sponsored retirement plans or through broker-dealers, financial institutions, and insurance companies. Additionally, advisory or fee-based programs sponsored by a broker-dealer or financial institution, such as a bank or trust company, may, by agreement with the Distributor or MML Advisers, make available to its program participants one or more of the above share classes.

Class R4, Class A, Class R3, and Class Y shares are offered primarily through other distribution channels, such as broker-dealers or financial institutions.

Class I, Class A, and Class Y shares may be purchased by individual investors through a financial intermediary or through a product sponsored by a financial intermediary.

• **Investment Accounts and Plans:** Class I, Class R5, Service Class, Administrative Class, Class R4, Class A, and Class R3 shares are available for purchase by insurance company separate investment accounts, qualified plans under Section 401(a) of the Code, Code Section 403(b) plans, Code Section 457 plans, non-qualified deferred compensation plans, and other institutional investors.

• **Funds:** Class I, Class R5, and Service Class shares are available for purchase by mutual funds and collective trust funds.

• **Section 501(c)(9) Associations:** Class R5, Class R4, Class A, and Class R3 shares may be purchased by voluntary employees' beneficiary associations described in Code Section 501(c)(9).

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• **Individual Retirement Accounts:** Class A shares of any Fund may be purchased by individual retirement accounts described in Code Section 408.

A plan or institutional investor will be permitted to purchase Class I, Class R5, Service Class, Administrative Class, Class R4, Class A, or Class R3 shares based upon the expected size (over time), servicing needs, or distribution or servicing costs for the plan or institutional investor as determined by the Distributor or a financial intermediary, as applicable.

A financial intermediary may, by agreement with the Distributor or MML Advisers, make available to its plan or institutional clients or its advisory or fee-based program participants shares of one class or a limited number of classes of the Funds. An investor should consult its financial intermediary for information (including expense information) regarding the share class(es) the intermediary will make available for purchase by the investor.

#### Additional Information Regarding Class A and Class Y Shares.
Present and former officers, directors, trustees, and employees (and their eligible family members) of each Fund, MassMutual and its affiliates, and

retirement plans established for the benefit of such individuals, are permitted to purchase Class A shares of each Fund.

Purchases of Class Y shares require an initial minimum investment of $100,000. For retirement plans, the investment minimum is $250 for each of the initial investment and subsequent investments for Class Y shares.

Class Y shares are sold at the NAV per share without a sales charge through financial intermediaries that have special agreements with MML Advisers or its affiliates or the Distributor for that purpose. A financial intermediary that buys Class Y shares for its customers' accounts may impose charges on those accounts. The procedures for buying, selling, exchanging, and transferring a Fund's other classes of shares (other than the time those orders must be received by the transfer agent) and some of the special account features available to investors buying other classes of shares do not apply to Class Y shares. Instructions for buying, selling, exchanging, or transferring Class Y shares must be submitted by a financial intermediary, not by its customers for whose benefit the shares are held.

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Sales Charges by Class

#### Initial Sales Charges
Class A shares are sold at their offering price, which is normally NAV plus an initial sales charge. However, in some cases, as described below, purchases are not subject to an initial sales charge, and the offering price will be the NAV. In other cases, reduced sales charges may be available, as described below. Out of the amount you invest, the Fund receives the NAV to invest for your account.

The sales charge varies depending on the amount of your purchase. A portion of the sales charge may be retained by the Distributor or allocated to your dealer as a concession. The Distributor reserves the right to reallow the entire sales charge as a concession to dealers. The current sales charge rates and concessions paid to dealers and brokers are as follows:

**Front-End Sales Charge (As a Percentage of Offering Price)/Front-End Sales Charge (As a Percentage of Net Amount Invested)/Concession (As a Percentage of Offering Price) for Different Purchase Amounts:** 

---

| | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|
| **Price <br>Breakpoints** | **General <br>Equity**  | **General <br>Equity**  | **General <br>Taxable <br>Bond**  | **General <br>Taxable <br>Bond**  | **Shorter-<br>Term <br>Bond**  | **Shorter-<br>Term <br>Bond**  |
| Less than $25,000 | 5.50 | %/ | 4.25 | %/ | 2.50 | %/ |
|  | 5.82 | %/ | 4.44 | %/ | 2.56 | %/ |
|  | 4.50 | % | 3.50 | % | 2.00 | % |
| $25000 – $49999 | 5.25 | %/ | 4.25 | %/ | 2.25 | %/ |
|  | 5.54 | %/ | 4.44 | %/ | 2.30 | %/ |
|  | 4.25 | % | 3.50 | % | 1.75 | % |
| $50000 – $99999 | 4.50 | %/ | 4.00 | %/ | 2.00 | %/ |
|  | 4.71 | %/ | 4.17 | %/ | 2.04 | %/ |
|  | 3.50 | % | 3.25 | % | 1.50 | % |
| $100000 – $249999 | 3.50 | %/ | 3.00 | %/ | 1.75 | %/ |
|  | 3.63 | %/ | 3.09 | %/ | 1.78 | %/ |
|  | 2.50 | % | 2.25 | % | 1.25 | % |
| $250000 – $499999 | 2.25 | %/ | 1.75 | %/ | 1.25 | %/ |
|  | 2.30 | %/ | 1.78 | %/ | 1.27 | %/ |
|  | 1.75 | % | 1.50 | % | 0.75 | % |
| $500000 – $999999 | 1.75 | %/ | 1.00 | %/ | 0.75 | %/ |
|  | 1.78 | %/ | 1.01 | %/ | 0.76 | %/ |
|  | 1.10 | % | 0.75 | % | 0.50 | % |
| $1,000,000 or more |  | / |  | / |  | / |
|  |  | / |  | / |  | / |
|  | 0.75 | % | 0.50 | % | 0.50 | % |

---

A reduced sales charge may be obtained for Class A shares under the Funds' "Rights of Accumulation" because of the economies of sales efforts and

reduction in expenses realized by the Distributor, dealers, and brokers making such sales.

To qualify for the lower sales charge rates that apply to larger purchases of Class A shares, you can add together:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Current purchases of Class A shares of more than one Fund subject to an initial sales charge to reduce the sales charge rate that applies to current purchases of Class A shares; and

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Class A shares of Funds you previously purchased subject to an initial or contingent deferred sales charge to reduce the sales charge rate for current purchases of Class A shares, provided that you still hold your investment in the previously purchased Funds.

The Distributor will add the value, at current offering price, of the Class A shares you previously purchased and currently own to the value of current purchases to determine the sales charge rate that applies. The reduced sales charge will apply only to current purchases. You must request the reduced sales charge when you buy Class A shares and inform your broker-dealer or other financial intermediary of Class A shares of any other Funds that you own. Information regarding reduced sales charges can be found on the MassMutual website at https://www.massmutual.com/funds.

#### Contingent Deferred Sales Charges
There is no initial sales charge on purchases of Class A shares of any one or more of the Funds aggregating $1 million or more. The Distributor pays dealers of record concessions in an amount equal to 0.75%, or 0.50% of purchases of $1 million or more, as shown in the above table. The concession will not be paid on purchases of shares by exchange or that were previously subject to a front-end sales charge and dealer concession.

If you redeem any of those shares within a holding period of 18 months from the date of their purchase, a contingent deferred sales charge of 1.00% will be deducted from the redemption proceeds (unless you are eligible for a waiver of that sales charge based on the categories listed below and you advise the transfer agent or another intermediary of your eligibility for the waiver when you place your redemption request).

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All contingent deferred sales charges will be based on the lesser of the NAV of the redeemed shares at the time of redemption or the original NAV. A contingent deferred sales charge is not imposed on:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; the amount of your account value represented by an increase in NAV over the initial purchase price,

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; shares purchased by the reinvestment of dividends or capital gains distributions, or

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; shares redeemed in the special circumstances described below.

To determine whether a contingent deferred sales charge applies to a redemption, the Fund redeems shares in the following order:

1. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; shares acquired by reinvestment of dividends and capital gains distributions, and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

2. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; shares held the longest.

Contingent deferred sales charges are not charged when you exchange shares of the Fund for shares of any other Fund. However, if you exchange them within the applicable contingent deferred sales charge holding period, the holding period will carry over to the Fund whose shares you acquire. Similarly, if you acquire shares of a Fund by exchanging shares of another Fund that are still subject to a contingent deferred sales charge holding period, that holding period will carry over to the acquired Fund.

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Sales Charge Waivers by Class

#### Waivers of Class A Initial Sales Charges
The Class A sales charges will be waived for shares purchased in the following types of transactions:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Purchases into insurance company separate investment accounts.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Purchases into retirement plans or other employee benefit plans.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Purchases of Class A shares aggregating $1 million or more of any one or more of the Funds.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Purchases into accounts for which the broker-dealer of record has entered into a special agreement with the Distributor allowing this waiver.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Purchases into accounts for which no sales concession is paid to any broker-dealer or other financial intermediary at the time of sale.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to MassMutual or its affiliates.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to registered management investment companies or separate accounts of insurance companies having an agreement with MassMutual, MML Advisers, or the Distributor for that purpose.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares issued in plans of reorganization to which the Fund is a party.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to present or former officers, directors, trustees, or employees (and their "immediate families<sup>(1)</sup>") of the Fund, MassMutual, and its affiliates.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to a portfolio manager of the Fund.

#### Waivers of Class A Contingent Deferred Sales Charges
The Class A contingent deferred sales charges will not be applied to shares purchased in certain types of transactions or redeemed in certain circumstances described below.

A. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Waivers for Redemptions in Certain Cases.

The Class A contingent deferred sales charges will be waived for redemptions of shares in the following cases:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions from insurance company separate investment accounts.

(1) *&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The term "immediate family" refers to one's spouse, children, grandchildren, grandparents, parents, parents-in-law, brothers and sisters, sons- and daughters-in-law, a sibling's spouse, a spouse's siblings, aunts, uncles, nieces, and nephews; relatives by virtue of a remarriage (step-children, step-parents, etc.) are included.*

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions from retirement plans or other employee benefit plans.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions from accounts other than retirement plans following the death or disability of the last surviving shareholder, including a trustee of a grantor trust or revocable living trust for which the trustee is also the sole beneficiary. The death or disability must have occurred after the account was established, and for disability you must provide evidence of a determination of disability by the Social Security Administration.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions from accounts for which the broker-dealer of record has entered into a special agreement with the Distributor allowing this waiver.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions from accounts for which no sales concession was paid to any broker-dealer or other financial intermediary at the time of sale.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Redemptions of Class A shares under an automatic withdrawal plan from an account other than a retirement plan if the aggregate value of the redeemed shares does not exceed 10% of the account's value annually.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; In the case of an IRA, to make distributions required under a divorce or separation agreement described in Section 71(b) of the Code.

B. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Waivers for Shares Sold or Issued in Certain Transactions.

The contingent deferred sales charge is also waived on Class A shares sold or issued in the following cases:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to MassMutual or its affiliates.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to registered management investment companies or separate accounts of insurance companies having an agreement with MassMutual, MML Advisers, or the Distributor for that purpose.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares issued in plans of reorganization to which the Fund is a party.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to present or former officers, directors, trustees, or employees (and their "immediate families<sup>(1)</sup>") of the Fund, MassMutual, and its affiliates.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Shares sold to a present or former portfolio manager of the Fund.

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Distribution Plan, Shareholder Servicing, and Payments to Intermediaries

Shares of all classes of the Funds, other than Class A shares, are sold without a front-end sales charge, and none of the Funds' shares are subject to a deferred sales charge. Class A shares are sold at NAV per share plus an initial sales charge.

#### Rule 12b-1 fees.
The Funds have adopted a Rule 12b-1 Plan (the "Plan"). Under the Plan, a Fund may make payments at an annual rate of up to 0.25% of the average daily net assets attributable to its Class R4 shares and Class A shares, and up to 0.50% of the average daily net assets attributable to its Class R3 shares. The Plan is a compensation plan, under which the Funds make payments to the Distributor for the services it provides and for the expenses it bears in connection with the distribution of Class R4, Class A, and Class R3 shares, and for the servicing of Class R4, Class A, and Class R3 shareholders. Because Rule 12b-1 fees are paid out of the Funds' Class R4, Class A, and Class R3 assets on an ongoing basis, they will increase the cost of your investment and may cost you more than paying other types of sales loads. All Class R4, Class A, and Class R3 shareholders share in the expense of Rule 12b-1 fees paid by those classes. A Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

#### Shareholder servicing payments.
MML Advisers pays all or a portion of the administrative and shareholder services fee it receives from each Fund, as described above under "Management of the Funds – Investment Adviser," to intermediaries as compensation for, or reimbursement of expenses relating to, services provided to shareholders of the Funds.

#### Payments to intermediaries.
The Distributor and MML Advisers may make payments to financial intermediaries for distribution and/or shareholder services provided by them. Financial intermediaries are firms that, for compensation, sell shares of mutual funds, including the Funds, and/or provide certain administrative and account maintenance services to mutual fund shareholders. Financial intermediaries may include, among others, brokers, financial planners or advisers, banks, and insurance companies. In some cases, a financial intermediary

may hold its clients' Fund shares in nominee or street name. Shareholder services provided by a financial intermediary may (though they will not necessarily) include, among other things: processing and mailing trade confirmations, periodic statements, prospectuses, annual reports, semiannual reports, shareholder notices, and other SEC-required communications; capturing and processing tax data; issuing and mailing dividend checks to shareholders who have selected cash distributions; preparing record date shareholder lists for proxy solicitations; collecting and posting distributions to shareholder accounts; and establishing and maintaining systematic withdrawals and automated investment plans and shareholder account registrations.

The Distributor and MML Advisers may retain a portion of the Rule 12b-1 payments and/or shareholder servicing payments received by them, or they may pay the full amount to intermediaries. Rule 12b-1 fees may be paid to financial intermediaries in advance for the first year after Class R4, Class A, and Class R3 shares are sold. After the first year, those fees will be paid on a quarterly basis.

The compensation paid to a financial intermediary is typically paid continually over time, during the period when the intermediary's clients hold investments in the Funds. The amount of continuing compensation paid to different financial intermediaries for distribution and/or shareholder services varies. The compensation is typically a percentage of the value of the financial intermediary's clients' investments in the Funds or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the intermediary.

#### Additional information.
The Distributor may directly, or through an affiliate, pay a sales concession of up to 1.00% of the purchase price of Service Class, Administrative Class, Class R4, Class A, Class R3, and Class Y shares to broker-dealers or other financial intermediaries at the time of sale. However, the total amount paid to broker-dealers or other financial intermediaries at the time of sale, including any advance of Rule 12b-1 service fees or shareholder services fees, may not be more than 1.00% of the purchase price.

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In addition to the various payments described above, MML Advisers in its discretion may directly, or through an affiliate, pay up to 0.35% of the amount invested to intermediaries who provide services on behalf of shareholders of the Funds. This compensation is paid by MML Advisers from its own assets. The payments will be based on criteria established by MML Advisers and will be paid quarterly, in arrears.

MassMutual, the parent company of MML Advisers, pays to an affiliate of Empower Retirement, LLC ("Empower") an amount equal to the profit realized by MML Advisers with respect to shares beneficially owned by retirement plans through recordkeeping platforms maintained by Empower or an affiliate.

The Distributor, MML Advisers, or MassMutual may also directly, or through an affiliate, make payments, out of its own assets, to intermediaries, including broker-dealers, insurance agents, and other service providers, that relate to the sale of shares of the Funds or certain of MassMutual's variable annuity contracts for which the Funds are underlying investment options. This compensation may take the form of:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Payments to administrative service providers that provide enrollment, recordkeeping, and other services to pension plans;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Cash and non-cash benefits, such as bonuses and allowances or prizes and awards, for certain broker-dealers, administrative service providers, and MassMutual insurance agents;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Payments to intermediaries for, among other things, training of sales personnel, conference support, marketing, or other services provided

to promote awareness of MassMutual's products;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Payments to broker-dealers and other intermediaries that enter into agreements providing the Distributor with access to representatives of those firms or with other marketing or administrative services; and

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Payments under agreements with MassMutual not directly related to the sale of specific variable annuity contracts or the Funds, such as educational seminars and training or pricing services.

In some instances, compensation may be made available only to certain financial intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Funds' shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as the Financial Industry Regulatory Authority.

These compensation arrangements are not offered to all intermediaries and the terms of the arrangements may differ among intermediaries. These arrangements may provide an intermediary with an incentive to recommend one mutual fund over another, one share class over another, or one insurance or annuity contract over another. You may want to take these compensation arrangements into account when evaluating any recommendations regarding the Funds or any contract using the Funds as investment options. You may contact your intermediary to find out more information about the compensation they may receive in connection with your investment.

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Buying, Redeeming, and Exchanging Shares

The Funds sell their shares at a price equal to their NAV plus any initial sales charge that applies (see "Determining Net Asset Value" below). The Funds have authorized one or more broker-dealers or other intermediaries to receive purchase orders on their behalf. Such broker-dealers or other intermediaries may themselves designate other intermediaries to receive purchase orders on the Funds' behalf. Your purchase order will be priced at the next NAV calculated after your order is received in good order by the transfer agent, MML Advisers, such a broker-dealer, or another intermediary authorized for this purpose. If you purchase shares through a broker-dealer or other intermediary, then, in order for your purchase to be based on a Fund's next determined NAV, the broker-dealer or other intermediary must receive your request before the close of regular trading on the New York Stock Exchange ("NYSE") (normally, 4:00 p.m. Eastern time), and the broker-dealer or other intermediary must subsequently communicate the request properly to the Funds. Shares purchased through a broker-dealer or other intermediary may be subject to transaction and/or other fees. The Funds will suspend selling their shares during any period when the determination of NAV is suspended. The Funds can reject any purchase order and can suspend purchases if they believe it is in their best interest.

The Funds have authorized one or more broker-dealers or other intermediaries to receive redemption requests on their behalf. Such broker-dealers or other intermediaries may themselves designate other intermediaries to receive redemption requests on the Funds' behalf. The Funds redeem their shares at their next NAV computed after your redemption request is received by the transfer agent, MML Advisers, such a broker-dealer, or another intermediary. If you redeem shares through a broker-dealer or other intermediary, then, in order for your redemption price to be based on a Fund's next determined NAV, the broker-dealer or other intermediary must receive your request before the close of regular trading on the NYSE, and the broker-dealer or other intermediary must subsequently communicate the request properly to the Funds. Shares redeemed through a broker-dealer or other intermediary may be subject to transaction and/or other fees. You will usually receive payment for

your shares within seven days after your redemption request is received in good order. If, however, you request redemption of shares recently purchased by check, you may not receive payment until the check has been collected, which may take up to 15 days from time of purchase. Under unusual circumstances, the Funds can also suspend or postpone payment, when permitted by applicable law and regulations. The Funds' transfer agent may temporarily delay for more than seven days the disbursement of redemption proceeds from the Fund account of a "Specified Adult" (as defined in Financial Industry Regulatory Authority Rule 2165) based on a reasonable belief that financial exploitation of the Specified Adult has occurred, is occurring, has been attempted, or will be attempted, subject to certain conditions. Under normal circumstances, each Fund expects to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. Under stressed market conditions, a Fund may pay redemption proceeds using cash obtained through borrowing arrangements that may be available from time to time. To the extent consistent with applicable laws and regulations, the Funds reserve the right to satisfy all or a portion of a redemption request by distributing securities or other property in lieu of cash ("in-kind" redemptions), under both normal and stressed market conditions. Some Funds may be limited in their ability to use assets other than cash to meet redemption requests due to restrictions on ownership of their portfolio assets. The securities distributed in an in-kind redemption will be valued in the same manner as they are valued for purposes of computing the Fund's NAV. These securities are subject to market risk until they are sold and may increase or decrease in value prior to converting them into cash. You may incur brokerage and other transaction costs, and could incur a taxable gain or loss for income tax purposes when converting the securities to cash.

The USA PATRIOT Act may require a Fund, a financial intermediary, or its authorized designee to obtain certain personal information from you which will be used to verify your identity. If you do not provide the information, it may not be possible to open an account. If a Fund, a financial intermediary, or authorized designee is unable to

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verify your customer information, the Fund reserves the right to close your account or to take such other steps as it deems reasonable.

#### Risk of Substantial Redemptions.
If substantial numbers of shares in a Fund were to be redeemed at the same time or at approximately the same time, the Fund might be required to liquidate a significant portion of its investment portfolio quickly to meet the redemptions. A Fund might be forced to sell portfolio securities at prices or at times when it would otherwise not have sold them, resulting in a reduction in the Fund's NAV; in addition, a substantial reduction in the size of a Fund may make it difficult for the investment adviser or subadviser to execute its investment program successfully for the Fund for a period following the redemptions. Similarly, the prices of the portfolio securities of a Fund might be adversely affected if one or more other investment accounts managed by the investment adviser or subadviser in an investment style similar to that of the Fund were to experience substantial redemptions and those accounts were required to sell portfolio securities quickly or at an inopportune time.

#### Exchanges
Generally, you can exchange shares of one Fund for the same class of shares of another MassMutual Fund, *except in the case of the MassMutual U.S. Government Money Market Fund, MassMutual Total Return Bond Fund, and MM S&P 500*<sup>®</sup> *Index Fund and, with respect to certain series of the MassMutual Premier Funds, in those cases when exchanges are not permitted*, as described in the applicable Prospectus under **"Placing Transaction Orders—For Shareholders holding shares of theTrust prior to November 1, 2004."** Any share class of another series may be exchanged for Class R5 shares of the MassMutual U.S. Government Money Market Fund. If Class R5 shares of the MassMutual U.S. Government Money Market Fund are exchanged for Class A shares of another series, any sales charge applicable to those Class A shares will typically apply. For individual retirement accounts described in Code Section 408, Class R5 shares of the MassMutual U.S. Government Money Market Fund may only be exchanged for Class A shares of another series (in which case any sales charge applicable to those Class A shares will typically apply), Class R4 shares of the MassMutual Total Return Bond Fund and MM S&P 500 Index Fund may only be

exchanged for Class A shares of another series (in which case any sales charge applicable to those Class A shares will typically apply), and Class A shares of any other series may only be exchanged for Class R4 shares of the MassMutual Total Return Bond Fund and MM S&P 500 Index Fund. An exchange is treated as a sale of shares in one series and a purchase of shares in another series at the NAV next determined after the exchange request is received and accepted by the transfer agent, MML Advisers, a broker-dealer, or another intermediary authorized for this purpose. You can only exchange into shares of another series if you meet any qualification requirements of the series into which you seek to exchange (for example, shares of some series are not available to purchasers through certain investment channels, and some may be available only to certain types of shareholders). In addition, in limited circumstances, such as those described above, for certain series the share class available for exchange may not be the same share class as the series from which you are exchanging. Exchange requests involving a purchase into any series (except the MassMutual Strategic Bond Fund, MassMutual U.S. Government Money Market Fund, MassMutual Inflation-Protected and Income Fund, MassMutual Core Bond Fund, MassMutual Diversified Bond Fund, MassMutual Short-Duration Bond Fund, MassMutual High Yield Fund, MassMutual Global Floating Rate Fund, MassMutual Global Credit Income Opportunities Fund, and MassMutual Emerging Markets Debt Blended Total Return Fund), however, will not be accepted if you have already made a purchase followed by a redemption involving the same series within the last 60 days. This restriction does not apply to rebalancing trades executed by any of the MassMutual RetireSMART by JPMorgan Funds, MassMutual Select T. Rowe Price Retirement Funds, and MassMutual Target Allocation Funds. This restriction also does not apply to exchanges made pursuant to certain asset allocation programs, systematic exchange programs, and dividend exchange programs. If you place an order to exchange shares of one series for another through a broker-dealer or other intermediary then, in order for your exchange to be effected based on the series' next determined NAVs, the broker-dealer or other intermediary must receive your request before the close of regular trading on the NYSE, and the broker- dealer or other intermediary must subsequently communicate the request properly to the MassMutual Funds.

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Your right to exchange shares is subject to applicable regulatory requirements or contractual obligations. The Funds may limit, restrict, or refuse exchange purchases, if, in the opinion of MML Advisers:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; you have engaged in excessive trading;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; a Fund receives or expects simultaneous orders affecting significant portions of the Fund's assets;

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; a pattern of exchanges occurs which coincides with a market timing strategy; or

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; the Fund would be unable to invest the funds effectively based on its investment objectives and policies or if the Fund would be adversely affected.

The Funds reserve the right to modify or terminate the exchange privilege as described above on 60 days written notice.

The Funds do not accept purchase, redemption, or exchange orders or compute their NAVs on days when the NYSE is closed. This includes: weekends, Good Friday, and all federal holidays other than Columbus Day and Veterans Day. Certain foreign markets may be open on days when the Funds do not accept orders or price their shares. As a result, the NAV of a Fund's shares may change on days when you will not be able to buy or sell shares.

#### Transaction Orders by Telephone and in Writing
In general, you may purchase, exchange, or sell (redeem) shares on any business day through your financial intermediary or by contacting the transfer agent in writing or by telephone, as described below.

#### Transaction Orders by Telephone
Transaction orders placed by telephone will only be accepted if an *Application for Telephone Trading Privileges* has been completed and returned to State Street Bank and Trust Company ("State Street"), the Funds' transfer agent. You may obtain

an *Application for Telephone Trading Privileges* by contacting Shareholder Servicing at 1-877-766-0014. Persons electing to place transaction orders by telephone are able to do so through the following dedicated telephone number: MassMutual Select Funds Transaction Line, 1-800-860-2232.

#### Transaction Orders in Writing
If you do not want to utilize telephone privileges, you may place your shareholder trades by sending written instructions to State Street. Transaction orders placed in writing should be addressed to *State Street Bank and Trust Company, Attn: Transfer Agency Operations, Box 5493, Boston, MA 02206* and should include the following information:

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A letter of instruction signed by an authorized signer of the account detailing the fund name, account number, and trade details; including the trade type (purchase or redemption), and the dollar or share amount. The trade will be processed upon receiving the request in good order.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The signature on the letter of instructions must be guaranteed by an acceptable financial institution (such as a bank, broker, or savings and loan association) as defined under Rule 17Ad-15 of the Securities Exchange Act of 1934, as amended. If your financial institution belongs to one of the medallion guarantee programs, it must use the actual "Medallion Guaranteed" stamp.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; If applicable, a corporate resolution which states that the extract of the by-laws is true and complete and is in full force and effect.

• &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The resolution must be signed by the secretary. It must have a corporate seal or state that no seal exists. If there is no seal, the corporate resolution must be signed by an authorized signer with a medallion guaranteed stamp and must be dated within sixty (60) days of presentment to State Street.

#### How to Invest
Outlined below are various methods for buying shares of the Funds:

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|:---|:---|
| **Method**  | **Instructions**  |
| Through your financial intermediary | Your financial intermediary can help you establish your account and buy shares on your behalf. To receive the current trading day's price, your financial intermediary must receive your request in good order prior to the close of regular trading on the New York Stock Exchange, usually 4:00 p.m., Eastern time. Your financial intermediary may charge you fees for executing the purchase for you. |

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| |
|:---|
| **Method**  |
| By exchange You or your financial intermediary may acquire shares of a Fund for your account by exchanging shares you own in certain other funds advised by MML Advisers for shares of the same class of a Fund, subject to the conditions described in "Exchanges" above. In addition, you or your financial intermediary may exchange shares of a class of a Fund you own for shares of a different class of the same Fund, subject to the conditions described in "Exchanges." To exchange, send written instructions to the applicable Fund, at the address noted below<sup>(1)</sup> or call 1-800-860-2232. |
| By wire You may purchase shares of a Fund by wiring money from your bank account to your Fund account. Prior to sending wire transfers, please contact Shareholder Services at 1-800-860-2232 for specific wiring instructions and to facilitate prompt and accurate credit upon receipt of your wire. <br> To receive the current trading day's price, your wire, along with a valid account number, must be received in your Fund account prior to the close of regular trading on the New York Stock Exchange, usually 4:00 p.m., Eastern time.<br> If your initial purchase of shares is by wire, you must first complete a new account application and promptly mail it to MassMutual Select Funds – (Fund Name), at the address noted below.<sup>(1)</sup> After completing a new account application, please call 1-800-860-2232 to obtain your account number. Please include your account number on the wire. |
| By check To purchase shares of a Fund by check, make your check payable to 'MassMutual Select Funds'. Your checks should include the fund name which you would like to purchase along with your account number (if previously established). Your request should be mailed to the address listed below.<sup>(1)</sup> The Funds will accept purchases only in U.S. dollars drawn from U.S. financial institutions. Cashier's checks, third party checks, money orders, credit card convenience checks, cash or equivalents, or payments in foreign currencies are not acceptable forms of payment. |

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(1) Regular Mail: State Street Bank and Trust Company, Attn: MassMutual Transfer Agency, Mail Code JAB0321, Box 5493, Boston, MA 02206

Overnight Mail: State Street Bank and Trust Company, Attn: MassMutual Transfer Agency, Mail Code JAB0321, 1776 Heritage Drive, No. Quincy, MA 02171

Cost Basis Reporting

In the case of individuals holding shares in a Fund directly, upon the redemption or exchange of shares in a Fund, the Fund or, if a shareholder purchased shares through a financial intermediary, the financial intermediary generally will be required to provide the shareholder and the Internal Revenue Service ("IRS") with cost basis and certain other related tax information about the

Fund shares redeemed or exchanged. Please contact the Funds by calling 1-888-309-3539 or consult your financial intermediary, as appropriate, for more information regarding available methods for cost basis reporting and how to select or change a particular method. Please consult your tax adviser to determine which available cost basis method is best for you.

Frequent Trading Policies

Purchases and exchanges of shares of the Funds should be made for investment purposes only. The Funds discourage, and do not accommodate, excessive trading and/or market timing activity. Excessive trading and/or market timing activity involving the Funds can disrupt the management of the Funds. These disruptions, in turn, can result in increased expenses and can have an adverse effect on Fund performance.

The Trustees, on behalf of the Funds, have approved the policies and procedures adopted by MML Advisers to help identify those individuals or entities MML Advisers determines may be engaging in excessive trading and/or market timing activities. MML Advisers monitors trading activity to uniformly enforce its procedures. However, those who engage in such activities may employ a variety of techniques to avoid detection. Therefore,

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despite MML Advisers' efforts to prevent excessive trading and/or market timing trading activities, there can be no assurance that MML Advisers will be able to identify all those who trade excessively or employ a market timing strategy and curtail their trading in every instance.

The monitoring process involves scrutinizing transactions in fund shares that exceed certain monetary thresholds or numerical limits within a specified period of time. Trading activity identified by either, or a combination, of these factors, or as a result of any other information actually available at the time, will be evaluated to determine whether such activity might constitute excessive trading and/or market timing activity. When trading activity is determined by a Fund or MML Advisers, in their sole discretion, to be excessive in nature, certain account-related privileges, such as the ability to place purchase, redemption, and exchange orders over the internet, may be suspended for such account.

*Omnibus Account Limitations*. Omnibus accounts, in which shares are held in the name of an intermediary on behalf of multiple investors, are a common form of holding shares among retirement plans and other financial intermediaries such as broker-dealers, advisers, and third-party administrators. Not all omnibus accounts apply the policies and procedures adopted by the Funds and MML Advisers. Some omnibus accounts may have different or less restrictive policies and procedures regarding frequent trading, or no trading restrictions at all. If you hold your Fund shares through an omnibus account, that financial intermediary may impose its own restrictions or limitations to discourage excessive trading and/or market timing activity. You should consult your

financial intermediary to find out what trading restrictions, including limitations on exchanges, may apply. The Funds' ability to identify and deter excessive trading and/or market timing activities through omnibus accounts is limited, and the Funds' success in accomplishing the objectives of the policies concerning frequent trading of Fund shares in this context depends significantly upon the cooperation of the financial intermediaries. Because the Funds receive these orders on an aggregated basis and because the omnibus accounts may trade with numerous fund families with differing frequent trading policies, the Funds are limited in their ability to identify or deter those individuals or entities that may be engaging in excessive trading and/or market timing activities. While the Funds and MML Advisers encourage those financial intermediaries to apply the Funds' policies to their customers who invest indirectly in the Funds, the Funds and MML Advisers may need to rely on those intermediaries to monitor trading in good faith in accordance with its or the Funds' policies, since individual trades in omnibus accounts are often not disclosed to the Funds. While the Funds will generally monitor trading activity at the omnibus account level to attempt to identify excessive trading and/or market timing activity, reliance on intermediaries increases the risk that excessive trading and/or market timing activity may go undetected. If evidence of possible excessive trading and/or market timing activity is observed by the Funds, the financial intermediary that is the registered owner will be asked to review the account activity, and to confirm to the Funds that appropriate action has been taken to limit any excessive trading and/or market timing activity.

Determining Net Asset Value

The NAV of each Fund's shares is determined once daily as of the close of regular trading on the NYSE, on each Business Day. A "Business Day" is every day the NYSE is open. The NYSE normally closes at 4:00 p.m. Eastern Time, but may close earlier on some days. If the NYSE is scheduled to close early, the Business Day will be considered to end as of the time of the NYSE's scheduled close. A Fund will not treat an intraday disruption in NYSE trading or other event that causes an unscheduled closing of the NYSE as a close of business of the NYSE for these purposes; instead, MML Advisers will determine the fair value of a Fund's securities in accordance with MML

Advisers' fair valuation policy and procedures. The NYSE currently is not open for trading on New Year's Day, Martin Luther King, Jr. Day, President's Day, Good Friday, Memorial Day, Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving Day, and Christmas Day. Each Fund calculates the NAV of each of its classes of shares by dividing the total value of the assets attributable to that class, less the liabilities attributable to that class, by the number of shares of that class that are outstanding. On holidays and other days when the NYSE is closed, each Fund's NAV generally is not calculated and the Funds do not anticipate accepting buy

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or sell orders. However, the value of each Fund's assets may still be affected on such days to the extent that an Underlying Fund holds foreign securities that trade on days that foreign securities markets are open.

The NAV of each Fund is based upon the NAVs of its corresponding Underlying Funds. Shares of the Underlying Funds are valued at their closing NAVs as reported on each Business Day.

Certain Underlying Funds may invest in securities that are traded principally in foreign markets and that trade on weekends and other days when the Funds do not price their shares. As a result, the values of the Funds' portfolio securities may

change on days when the prices of the Funds' shares are not calculated. The prices of the Funds' shares will reflect any such changes when the prices of the Funds' shares are next calculated, which is the next Business Day.

The prospectuses and SAIs for the Underlying Funds explain the valuation methods for the Underlying Funds, including the circumstances under which the Underlying Funds may use fair value pricing and the effects of doing so. Such prospectuses and SAIs are available on the SEC's EDGAR database on its Internet site at http://www.sec.gov.

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Taxation and Distributions

Each Fund intends to qualify each year for treatment as a regulated investment company under Subchapter M of the Code. As a regulated investment company, a Fund will not be subject to U.S. federal income taxes on its ordinary income and net realized capital gains that are distributed in a timely manner to its shareholders. A Fund's failure to qualify as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders. In addition, a Fund that fails to distribute at least 98% of its ordinary income for a calendar year and 98.2% of its capital gain net income recognized during the one-year period ending October 31 plus any retained amount from the prior year generally will be subject to a non-deductible 4% excise tax on the undistributed amount.

Certain investors, including most tax-advantaged plan investors, may be eligible for preferential U.S. federal income tax treatment on distributions received from a Fund and dispositions of Fund shares. This Prospectus does not attempt to describe such preferential tax treatment. Any prospective investor that is a trust or other entity eligible for special tax treatment under the Code that is considering purchasing shares of a Fund, including either directly or in connection with a life insurance company separate investment account, should consult its tax advisers about the U.S. federal, state, local, and foreign tax consequences particular to it, as should persons considering whether to have amounts held for their benefit by such trusts or other entities in shares of a Fund.

Investors are generally subject to U.S. federal income taxes on distributions received in respect of their shares. Distributions are taxed to investors in the manner described herein whether distributed in cash or additional shares of the Fund. Taxes on distributions of capital gains are determined by how long the Fund or Underlying Fund owned (or is deemed to have owned) the investments that generated them, rather than by how long the shareholder held the shares. Distributions of a Fund's ordinary income and short-term capital gains (i.e., gains from capital assets held for one year or less) are taxable to a shareholder as ordinary income. Certain dividends may be eligible for the dividends-received deduction for corporate shareholders to the extent they are reported as

such. Dividends properly reported as capital gain dividends (relating to gains from the sale of capital assets held by a Fund or an Underlying Fund for more than one year) are taxable in the hands of an investor as long-term capital gain includible in net capital gain and taxed to individuals at reduced rates. Distributions of investment income reported by a Fund as derived from "qualified dividend income" will be taxed in the hands of individuals at the rates applicable to long-term capital gain, provided that holding period and other requirements are met at both the shareholder and Fund level. Distributions from REITs generally do not qualify as qualified dividend income.

The Code generally imposes a 3.8% Medicare contribution tax on the net investment income of certain individuals, trusts, and estates to the extent their income exceeds certain threshold amounts. For this purpose "net investment income" generally includes: (i) dividends paid by a Fund, including any capital gain dividends, and (ii) net capital gains recognized on the sale, redemption, exchange, or other taxable disposition of shares of a Fund. Shareholders are advised to consult their tax advisers regarding the possible implications of this additional tax on their investment in a Fund.

The nature of each Fund's distributions will be affected by its investment strategies and those of the Underlying Funds in which it invests. A Fund that invests primarily in Underlying Funds whose investment return consists largely of interest, dividends, and capital gains from short-term holdings will distribute largely ordinary income. A Fund whose return comes largely from its sale or the sale by Underlying Funds of long-term holdings will distribute largely capital gain dividends. Distributions are taxable to a shareholder even though they are paid from income or gains earned by a Fund prior to the shareholder's investment and thus were included in the price paid by the shareholder for his or her shares.

Each Fund intends to pay out as dividends substantially all of its net investment income (which comes from dividends and any interest it receives from its investments). Each Fund also intends to distribute substantially all of its net realized

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long- and short-term capital gains, if any, after giving effect to any available capital loss carryforwards. For each Fund, distributions, if any, are declared and paid at least annually. Distributions may be taken either in cash or in additional shares of the respective Fund at the Fund's NAV on the first Business Day after the record date for the distribution, at the option of the shareholder. A shareholder that itself qualifies as a regulated investment company is permitted to report a portion of its distributions as "qualified dividend income," provided certain requirements are met.

Any gain resulting from an exchange or redemption of an investor's shares in a Fund will generally be subject to tax as long-term or short-term capital gain. A loss incurred with respect to the disposition of shares of a Fund held for six months or less will be treated as a long-term capital loss to the extent of long-term capital gains dividends received with respect to such shares.

A Fund's investments in Underlying Funds can cause the tax treatment of the Fund's gains, losses, and distributions to differ from the tax treatment that would apply if either the Fund invested directly in the types of securities held by the Underlying Funds or the Fund's shareholders invested directly in the Underlying Funds. As a result, investors may receive taxable distributions earlier and recognize higher amounts of capital gain or ordinary income than they otherwise would.

An Underlying Fund's investments in foreign securities may be subject to foreign withholding or other taxes. In that case, the Underlying Fund's yield on those securities would be decreased. A Fund may be able to elect to "pass through" to its shareholders foreign income taxes paid by certain Underlying Funds. If a Fund so elects, a shareholder of the Fund must include its share of those taxes in gross income as a distribution from the Fund and the shareholder will be allowed to claim a credit (or a deduction, if the shareholder itemizes deductions) for such amounts on its U.S. federal tax return subject to certain limitations. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Fund through tax-advantaged accounts (including those who invest through individual retirement accounts or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit

or deduction passed through by a Fund. A shareholder that itself qualifies for treatment as a regulated investment company and that qualifies as a "qualified fund of funds" may elect to pass through to its shareholders a tax credit or deduction passed through by a Fund.

In addition, a Fund's or Underlying Fund's investments in foreign securities, fixed income securities, derivatives, or foreign currencies may increase or accelerate the Fund's recognition of ordinary income and may affect the timing, amount, or character of the Fund's distributions. Certain of a Fund's or Underlying Fund's investments, including certain debt instruments, could cause the Fund or Underlying Fund to recognize taxable income in excess of the cash generated by such investments; a Fund or Underlying Fund could be required to sell other investments, including when not otherwise advantageous to do so, in order to make required distributions.

Distributions by a Fund to shareholders that are not "United States persons" within the meaning of the Code ("foreign persons") properly reported by the Fund as (i) capital gain dividends, (ii) "interest-related dividends" (i.e., U.S.-source interest income that, in general, would not be subject to U.S. federal income tax if earned directly by an individual foreign shareholder), and (iii) "short-term capital gain dividends" (i.e., net short-term capital gains in excess of net long-term capital losses), in each case to the extent such distributions were properly reported as such by the Fund generally are not subject to withholding of U.S. federal income tax. Distributions by a Fund to foreign persons other than capital gain dividends, interest-related dividends, and short-term capital gain dividends generally are subject to withholding of U.S. federal income tax at a rate of 30% (or lower applicable treaty rate). Foreign persons should refer to the SAI for further information, and should consult their tax advisors as to the tax consequences to them of owning Fund shares.

The discussion above is very general. Shareholders should consult their tax advisers for more information about the effect that an investment in a Fund could have on their own tax situations, including possible U.S. federal, state, local, and foreign taxes. Also, as noted above, this discussion does not apply to Fund shares held through tax-advantaged retirement plans.

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***Financial Highlights***

The financial highlights tables are intended to help you understand the Funds' financial performance for the past 5 years (or shorter periods for newer Funds). Since Class Y shares commenced operations on February 1, 2023, financial highlights are not yet presented for this class. Certain information reflects financial results for a single Fund share. The total returns in the tables represent the rate that an investor would have earned on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Deloitte & Touche LLP, an independent registered public accounting firm, whose reports, along with each Fund's financial statements, are included in the Trust's Annual Reports, and are incorporated by reference into the SAI, and are available upon request.

**MASSMUTUAL 20/80 ALLOCATION FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.60** | $0.32 | $(1.84) | $(1.52) | $(0.33) | $(0.38) | $(0.71) | **$8.37** | (15.46%) | $13143 | 0.12% | 0.04% | 3.35% |
| 9/30/21 | **10.34** | 0.28 | 0.56 | 0.84 | (0.38) | (0.20) | (0.58) | **10.60** | 8.35% | 18990 | 0.12% | 0.03% | 2.67% |
| 9/30/20 | **10.15** | 0.25 | 0.45 | 0.70 | (0.31) | (0.20) | (0.51) | **10.34** | 7.09% | 17848 | 0.11% | 0.02% | 2.49% |
| 9/30/19 | **10.02** | 0.27 | 0.37 | 0.64 | (0.32) | (0.19) | (0.51) | **10.15** | 6.95% | 12197 | 0.12% | 0.02% | 2.78% |
| 9/30/18 | **10.04** | 0.23 | 0.04 | 0.27 | (0.29) |  | (0.29) | **10.02** | 2.71% | 8431 | 0.12% | 0.02% | 2.27% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.59** | $0.45 | $(1.99) | $(1.54) | $(0.32) | $(0.38) | $(0.70) | **$8.35** | (15.64%) | $2488 | 0.22% | 0.14% | 4.59% |
| 9/30/21 | **10.32** | 0.27 | 0.57 | 0.84 | (0.37) | (0.20) | (0.57) | **10.59** | 8.37% | 6108 | 0.22% | 0.13% | 2.62% |
| 9/30/20 | **10.14** | 0.28 | 0.40 | 0.68 | (0.30) | (0.20) | (0.50) | **10.32** | 6.89% | 5946 | 0.21% | 0.12% | 2.85% |
| 9/30/19 | **10.01** | 0.29 | 0.34 | 0.63 | (0.31) | (0.19) | (0.50) | **10.14** | 6.83% | 6919 | 0.22% | 0.12% | 2.96% |
| 9/30/18 | **10.02** | 0.34 | (0.07) | 0.27 | (0.28) |  | (0.28) | **10.01** | 2.72% | 7023 | 0.22% | 0.13% | 3.45% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.58** | $0.28 | $(1.82) | $(1.54) | $(0.31) | $(0.38) | $(0.69) | **$8.35** | (15.66%) | $103035 | 0.32% | 0.24% | 2.95% |
| 9/30/21 | **10.32** | 0.24 | 0.59 | 0.83 | (0.37) | (0.20) | (0.57) | **10.58** | 8.21% | 123549 | 0.32% | 0.23% | 2.27% |
| 9/30/20 | **10.13** | 0.05 | 0.63 | 0.68 | (0.29) | (0.20) | (0.49) | **10.32** | 6.90% | 114464 | 0.31% | 0.22% | 0.51% |
| 9/30/19 | **10.01** | 0.27 | 0.34 | 0.61 | (0.30) | (0.19) | (0.49) | **10.13** | 6.62% | 9225 | 0.32% | 0.22% | 2.74% |
| 9/30/18 | **10.02** | 0.23 | 0.03 | 0.26 | (0.27) |  | (0.27) | **10.01** | 2.61% | 7882 | 0.32% | 0.22% | 2.27% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.60** | $0.28 | $(1.84) | $(1.56) | $(0.28) | $(0.38) | $(0.66) | **$8.38** | (15.72%) | $18215 | 0.42% | 0.34% | 2.88% |
| 9/30/21 | **10.33** | 0.25 | 0.57 | 0.82 | (0.35) | (0.20) | (0.55) | **10.60** | 8.11% | 26944 | 0.42% | 0.33% | 2.40% |
| 9/30/20 | **10.14** | 0.22 | 0.44 | 0.66 | (0.27) | (0.20) | (0.47) | **10.33** | 6.72% | 34036 | 0.41% | 0.32% | 2.17% |
| 9/30/19 | **10.01** | 0.28 | 0.33 | 0.61 | (0.29) | (0.19) | (0.48) | **10.14** | 6.57% | 32206 | 0.42% | 0.32% | 2.87% |
| 9/30/18 | **10.02** | 0.27 | (0.02) | 0.25 | (0.26) |  | (0.26) | **10.01** | 2.50% | 39271 | 0.42% | 0.33% | 2.72% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.76** | $0.27 | $(1.87) | $(1.60) | $(0.27) | $(0.38) | $(0.65) | **$8.51** | (15.92%) | $3066 | 0.57% | 0.49% | 2.80% |
| 9/30/21 | **10.21** | 0.26 | 0.55 | 0.81 | (0.06) | (0.20) | (0.26) | **10.76** | 8.00% | 4254 | 0.57% | 0.48% | 2.46% |
| 9/30/20 | **10.04** | 0.39 | 0.25 | 0.64 | (0.27) | (0.20) | (0.47) | **10.21** | 6.51% | 6643 | 0.56% | 0.47% | 3.94% |
| 9/30/19 | **9.92** | 0.24 | 0.35 | 0.59 | (0.28) | (0.19) | (0.47) | **10.04** | 6.42% | 124050 | 0.57% | 0.47% | 2.47% |
| 9/30/18 | **9.94** | 0.22 | 0.01 | 0.23 | (0.25) |  | (0.25) | **9.92** | 2.31% | 106763 | 0.57% | 0.48% | 2.24% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.65** | $0.26 | $(1.84) | $(1.58) | $(0.27) | $(0.38) | $(0.65) | **$8.42** | (15.90%) | $14202 | 0.67% | 0.59% | 2.69% |
| 9/30/21 | **10.38** | 0.22 | 0.57 | 0.79 | (0.32) | (0.20) | (0.52) | **10.65** | 7.76% | 19773 | 0.67% | 0.58% | 2.08% |
| 9/30/20 | **10.19** | 0.23 | 0.41 | 0.64 | (0.25) | (0.20) | (0.45) | **10.38** | 6.45% | 22073 | 0.66% | 0.57% | 2.30% |
| 9/30/19 | **10.05** | 0.25 | 0.34 | 0.59 | (0.26) | (0.19) | (0.45) | **10.19** | 6.34% | 25898 | 0.67% | 0.57% | 2.59% |
| 9/30/18 | **10.05** | 0.23 | 0.00<sup>d</sup> | 0.23 | (0.23) |  | (0.23) | **10.05** | 2.30% | 27681 | 0.67% | 0.58% | 2.25% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.45** | $0.24 | $(1.81) | $(1.57) | $(0.25) | $(0.38) | $(0.63) | **$8.25** | (16.05%) | $4126 | 0.82% | 0.74% | 2.49% |
| 9/30/21 | **10.20** | 0.21 | 0.56 | 0.77 | (0.32) | (0.20) | (0.52) | **10.45** | 7.64% | 5725 | 0.82% | 0.73% | 2.06% |
| 9/30/20 | **10.01** | 0.21 | 0.41 | 0.62 | (0.23) | (0.20) | (0.43) | **10.20** | 6.32% | 6964 | 0.81% | 0.72% | 2.11% |
| 9/30/19 | **9.89** | 0.22 | 0.34 | 0.56 | (0.25) | (0.19) | (0.44) | **10.01** | 6.15% | 7102 | 0.82% | 0.72% | 2.30% |
| 9/30/18 | **9.91** | 0.20 | 0.01 | 0.21 | (0.23) |  | (0.23) | **9.89** | 2.10% | 7635 | 0.82% | 0.73% | 2.03% |

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– 228 –

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 27% | 26% | 33% | 39% | 62% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*d* &nbsp;&nbsp;&nbsp;&nbsp;*Amount is less than $0.005 per share.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 229 –

**MASSMUTUAL 40/60 ALLOCATION FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.57** | $0.27 | $(1.85) | $(1.58) | $(0.33) | $(0.55) | $(0.88) | **$8.11** | (16.39%) | $30477 | 0.11% | 0.06% | 2.83% |
| 9/30/21 | **9.80** | 0.22 | 1.11 | 1.33 | (0.33) | (0.23) | (0.56) | **10.57** | 13.89% | 47449 | 0.11% | 0.05% | 2.09% |
| 9/30/20 | **9.93** | 0.18 | 0.71 | 0.89 | (0.24) | (0.78) | (1.02) | **9.80** | 9.29% | 36725 | 0.10% | 0.04% | 1.94% |
| 9/30/19 | **10.58** | 0.21 | 0.13 | 0.34 | (0.31) | (0.68) | (0.99) | **9.93** | 4.69% | 28843 | 0.10% | 0.04% | 2.13% |
| 9/30/18 | **10.31** | 0.16 | 0.47 | 0.63 | (0.34) | (0.02) | (0.36) | **10.58** | 6.21% | 12666 | 0.09% | 0.05% | 1.50% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.57** | $0.34 | $(1.92) | $(1.58) | $(0.32) | $(0.55) | $(0.87) | **$8.12** | (16.37%) | $5503 | 0.21% | 0.16% | 3.59% |
| 9/30/21 | **9.81** | 0.23 | 1.08 | 1.31 | (0.32) | (0.23) | (0.55) | **10.57** | 13.66% | 8580 | 0.21% | 0.15% | 2.23% |
| 9/30/20 | **9.94** | 0.22 | 0.65 | 0.87 | (0.22) | (0.78) | (1.00) | **9.81** | 9.12% | 9331 | 0.20% | 0.14% | 2.34% |
| 9/30/19 | **10.57** | 0.28 | 0.06 | 0.34 | (0.29) | (0.68) | (0.97) | **9.94** | 4.76% | 9972 | 0.20% | 0.14% | 2.88% |
| 9/30/18 | **10.31** | 0.29 | 0.32 | 0.61 | (0.33) | (0.02) | (0.35) | **10.57** | 6.01% | 25611 | 0.19% | 0.15% | 2.78% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.62** | $0.23 | $(1.82) | $(1.59) | $(0.31) | $(0.55) | $(0.86) | **$8.17** | (16.40%) | $12834 | 0.31% | 0.26% | 2.43% |
| 9/30/21 | **9.85** | 0.21 | 1.10 | 1.31 | (0.31) | (0.23) | (0.54) | **10.62** | 13.62% | 16971 | 0.31% | 0.25% | 2.06% |
| 9/30/20 | **9.98** | 0.13 | 0.73 | 0.86 | (0.21) | (0.78) | (0.99) | **9.85** | 8.98% | 17683 | 0.30% | 0.24% | 1.37% |
| 9/30/19 | **10.62** | 0.23 | 0.10 | 0.33 | (0.29) | (0.68) | (0.97) | **9.98** | 4.53% | 11427 | 0.30% | 0.24% | 2.35% |
| 9/30/18 | **10.35** | 0.10 | 0.51 | 0.61 | (0.32) | (0.02) | (0.34) | **10.62** | 5.97% | 11330 | 0.29% | 0.25% | 0.96% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.61** | $0.22 | $(1.83) | $(1.61) | $(0.29) | $(0.55) | $(0.84) | **$8.16** | (16.55%) | $28220 | 0.41% | 0.36% | 2.30% |
| 9/30/21 | **9.84** | 0.21 | 1.09 | 1.30 | (0.30) | (0.23) | (0.53) | **10.61** | 13.46% | 44399 | 0.41% | 0.35% | 2.02% |
| 9/30/20 | **9.96** | 0.19 | 0.67 | 0.86 | (0.20) | (0.78) | (0.98) | **9.84** | 8.94% | 53133 | 0.40% | 0.34% | 1.98% |
| 9/30/19 | **10.59** | 0.23 | 0.09 | 0.32 | (0.27) | (0.68) | (0.95) | **9.96** | 4.50% | 70893 | 0.40% | 0.34% | 2.40% |
| 9/30/18 | **10.32** | 0.23 | 0.37 | 0.60 | (0.31) | (0.02) | (0.33) | **10.59** | 5.86% | 87160 | 0.39% | 0.35% | 2.18% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.51** | $0.20 | $(1.80) | $(1.60) | $(0.29) | $(0.55) | $(0.84) | **$8.07** | (16.65%) | $32058 | 0.56% | 0.51% | 2.14% |
| 9/30/21 | **9.75** | 0.17 | 1.10 | 1.27 | (0.28) | (0.23) | (0.51) | **10.51** | 13.27% | 32786 | 0.56% | 0.50% | 1.65% |
| 9/30/20 | **9.88** | 0.18 | 0.67 | 0.85 | (0.20) | (0.78) | (0.98) | **9.75** | 8.87% | 29626 | 0.55% | 0.49% | 1.96% |
| 9/30/19 | **10.53** | 0.19 | 0.10 | 0.29 | (0.26) | (0.68) | (0.94) | **9.88** | 4.19% | 40232 | 0.55% | 0.49% | 2.02% |
| 9/30/18 | **10.26** | 0.18 | 0.41 | 0.59 | (0.30) | (0.02) | (0.32) | **10.53** | 5.80% | 34455 | 0.54% | 0.50% | 1.69% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.64** | $0.20 | $(1.84) | $(1.64) | $(0.27) | $(0.55) | $(0.82) | **8.18** | (16.82%) | $45256 | 0.66% | 0.61% | 2.10% |
| 9/30/21 | **9.86** | 0.18 | 1.10 | 1.28 | (0.27) | (0.23) | (0.50) | **10.64** | 13.26% | 61814 | 0.66% | 0.60% | 1.73% |
| 9/30/20 | **9.99** | 0.16 | 0.67 | 0.83 | (0.18) | (0.78) | (0.96) | **9.86** | 8.56% | 69682 | 0.65% | 0.59% | 1.67% |
| 9/30/19 | **10.61** | 0.21 | 0.09 | 0.30 | (0.24) | (0.68) | (0.92) | **9.99** | 4.24% | 81959 | 0.65% | 0.59% | 2.13% |
| 9/30/18 | **10.34** | 0.20 | 0.37 | 0.57 | (0.28) | (0.02) | (0.30) | **10.61** | 5.56% | 91459 | 0.64% | 0.60% | 1.90% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.50** | $0.21 | $(1.83) | $(1.62) | $(0.30) | $(0.55) | $(0.85) | **$8.03** | (16.91%) | $15309 | 0.81% | 0.76% | 2.25% |
| 9/30/21 | **9.74** | 0.17 | 1.08 | 1.25 | (0.26) | (0.23) | (0.49) | **10.50** | 13.07% | 7450 | 0.81% | 0.75% | 1.69% |
| 9/30/20 | **9.86** | 0.14 | 0.68 | 0.82 | (0.16) | (0.78) | (0.94) | **9.74** | 8.56% | 8785 | 0.80% | 0.74% | 1.46% |
| 9/30/19 | **10.50** | 0.18 | 0.09 | 0.27 | (0.23) | (0.68) | (0.91) | **9.86** | 3.95% | 9050 | 0.80% | 0.74% | 1.90% |
| 9/30/18 | **10.24** | 0.18 | 0.37 | 0.55 | (0.27) | (0.02) | (0.29) | **10.50** | 5.46% | 11230 | 0.79% | 0.75% | 1.73% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 32% | 24% | 52% | 43% | 52% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 230 –

**MASSMUTUAL 60/40 ALLOCATION FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.96** | $0.19 | $(1.73) | $(1.54) | $(0.38) | $(1.02) | $(1.40) | **$8.02** | (16.45%) | $28473 | 0.12% | 0.06% | 2.05% |
| 9/30/21 | **9.50** | 0.19 | 1.70 | 1.89 | (0.28) | (0.15) | (0.43) | **10.96** | 20.32% | 28917 | 0.11% | 0.05% | 1.81% |
| 9/30/20 | **9.90** | 0.16 | 0.71 | 0.87 | (0.21) | (1.06) | (1.27) | **9.50** | 9.14% | 21696 | 0.11% | 0.04% | 1.73% |
| 9/30/19 | **11.21** | 0.21 | (0.12)<sup>aa</sup> | 0.09 | (0.32) | (1.08) | (1.40) | **9.90** | 3.17% | 15679 | 0.11% | 0.04% | 2.19% |
| 9/30/18 | **10.77** | 0.20 | 0.75 | 0.95 | (0.40) | (0.11) | (0.51) | **11.21** | 9.07% | 8011 | 0.10% | 0.06% | 1.84% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.96** | $0.32 | $(1.86) | $(1.54) | $(0.37) | $(1.02) | $(1.39) | **$8.03** | (16.42%) | $8300 | 0.21% | 0.16% | 3.24% |
| 9/30/21 | **9.50** | 0.16 | 1.72 | 1.88 | (0.27) | (0.15) | (0.42) | **10.96** | 20.21% | 20602 | 0.21% | 0.15% | 1.56% |
| 9/30/20 | **9.91** | 0.18 | 0.67 | 0.85 | (0.20) | (1.06) | (1.26) | **9.50** | 8.93% | 15435 | 0.21% | 0.14% | 1.92% |
| 9/30/19 | **11.21** | 0.22 | (0.14)<sup>aa</sup> | 0.08 | (0.30) | (1.08) | (1.38) | **9.91** | 3.12% | 12028 | 0.21% | 0.14% | 2.21% |
| 9/30/18 | **10.77** | 0.29 | 0.65 | 0.94 | (0.39) | (0.11) | (0.50) | **11.21** | 8.96% | 13583 | 0.20% | 0.16% | 2.60% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.01** | $0.19 | $(1.75) | $(1.56) | $(0.36) | $(1.02) | $(1.38) | **$8.07** | (16.55%) | $20361 | 0.32% | 0.26% | 2.00% |
| 9/30/21 | **9.54** | 0.17 | 1.71 | 1.88 | (0.26) | (0.15) | (0.41) | **11.01** | 20.15% | 24617 | 0.31% | 0.25% | 1.60% |
| 9/30/20 | **9.93** | 0.07 | 0.79 | 0.86 | (0.19) | (1.06) | (1.25) | **9.54** | 8.94% | 25087 | 0.31% | 0.24% | 0.76% |
| 9/30/19 | **11.24** | 0.20 | (0.14)<sup>aa</sup> | 0.06 | (0.29) | (1.08) | (1.37) | **9.93** | 2.90% | 9014 | 0.31% | 0.24% | 2.03% |
| 9/30/18 | **10.80** | 0.11 | 0.82 | 0.93 | (0.38) | (0.11) | (0.49) | **11.24** | 8.81% | 8522 | 0.30% | 0.25% | 1.01% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.00** | $0.19 | $(1.76) | $(1.57) | $(0.34) | $(1.02) | $(1.36) | **$8.07** | (16.62%) | $37871 | 0.41% | 0.36% | 1.98% |
| 9/30/21 | **9.53** | 0.16 | 1.71 | 1.87 | (0.25) | (0.15) | (0.40) | **11.00** | 20.00% | 61143 | 0.41% | 0.35% | 1.53% |
| 9/30/20 | **9.92** | 0.16 | 0.68 | 0.84 | (0.17) | (1.06) | (1.23) | **9.53** | 8.78% | 59725 | 0.41% | 0.34% | 1.71% |
| 9/30/19 | **11.22** | 0.21 | (0.15)<sup>aa</sup> | 0.06 | (0.28) | (1.08) | (1.36) | **9.92** | 2.88% | 81829 | 0.41% | 0.34% | 2.11% |
| 9/30/18 | **10.79** | 0.19 | 0.72 | 0.91 | (0.37) | (0.11) | (0.48) | **11.22** | 8.62% | 93858 | 0.40% | 0.36% | 1.75% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.91** | $0.16 | $(1.74) | $(1.58) | $(0.32) | $(1.02) | $(1.34) | **$7.99** | (16.78%) | $8037 | 0.56% | 0.51% | 1.72% |
| 9/30/21 | **9.43** | 0.13 | 1.71 | 1.84 | (0.21) | (0.15) | (0.36) | **10.91** | 19.83% | 10735 | 0.56% | 0.50% | 1.26% |
| 9/30/20 | **9.84** | 0.20 | 0.62 | 0.82 | (0.17) | (1.06) | (1.23) | **9.43** | 8.59% | 10218 | 0.56% | 0.49% | 2.13% |
| 9/30/19 | **11.14** | 0.18 | (0.13)<sup>aa</sup> | 0.05 | (0.27) | (1.08) | (1.35) | **9.84** | 2.75% | 27212 | 0.56% | 0.49% | 1.87% |
| 9/30/18 | **10.72** | 0.16 | 0.73 | 0.89 | (0.36) | (0.11) | (0.47) | **11.14** | 8.47% | 24118 | 0.55% | 0.51% | 1.46% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.04** | $0.16 | $(1.76) | $(1.60) | $(0.32) | $(1.02) | $(1.34) | **$8.10** | (16.84%) | $44420 | 0.66% | 0.61% | 1.69% |
| 9/30/21 | **9.57** | 0.14 | 1.70 | 1.84 | (0.22) | (0.15) | (0.37) | **11.04** | 19.60% | 57203 | 0.66% | 0.60% | 1.31% |
| 9/30/20 | **9.96** | 0.13 | 0.69 | 0.82 | (0.15) | (1.06) | (1.21) | **9.57** | 8.51% | 59454 | 0.66% | 0.59% | 1.43% |
| 9/30/19 | **11.24** | 0.19 | (0.14)<sup>aa</sup> | 0.05 | (0.25) | (1.08) | (1.33) | **9.96** | 2.67% | 65910 | 0.66% | 0.59% | 1.90% |
| 9/30/18 | **10.80** | 0.17 | 0.72 | 0.89 | (0.34) | (0.11) | (0.45) | **11.24** | 8.42% | 77780 | 0.65% | 0.61% | 1.54% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.84** | $0.15 | $(1.74) | $(1.59) | $(0.29) | $(1.02) | $(1.31) | **$7.94** | (17.00%) | $9592 | 0.81% | 0.76% | 1.53% |
| 9/30/21 | **9.40** | 0.12 | 1.68 | 1.80 | (0.21) | (0.15) | (0.36) | **10.84** | 19.50% | 14252 | 0.81% | 0.75% | 1.13% |
| 9/30/20 | **9.80** | 0.11 | 0.68 | 0.79 | (0.13) | (1.06) | (1.19) | **9.40** | 8.33% | 15686 | 0.81% | 0.74% | 1.16% |
| 9/30/19 | **11.10** | 0.16 | (0.13)<sup>aa</sup> | 0.03 | (0.25) | (1.08) | (1.33) | **9.80** | 2.45% | 16144 | 0.81% | 0.74% | 1.66% |
| 9/30/18 | **10.69** | 0.13 | 0.73 | 0.86 | (0.34) | (0.11) | (0.45) | **11.10** | 8.21% | 16492 | 0.80% | 0.76% | 1.16% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 26% | 28% | 58% | 44% | 55% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return does not reflect expenses that apply at the separate account level or to related insurance products. Inclusion of these charges would reduce the total return figures for all periods shown.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 231 –

**MASSMUTUAL 80/20 ALLOCATION FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.13** | $0.20 | $(2.08) | $(1.88) | $(0.41) | $(0.98) | $(1.39) | **$8.86** | (17.85%) | $33246 | 0.16% | 0.09% | 1.91% |
| 9/30/21 | **10.28** | 0.18 | 2.24 | 2.42 | (0.23) | (0.34) | (0.57) | **12.13** | 24.09% | 38991 | 0.16% | 0.08% | 1.51% |
| 9/30/20 | **10.59** | 0.16 | 0.86 | 1.02 | (0.19) | (1.14) | (1.33) | **10.28** | 9.81% | 30942 | 0.18% | 0.07% | 1.58% |
| 9/30/19 | **12.25** | 0.21 | (0.27) | (0.06) | (0.34) | (1.26) | (1.60) | **10.59** | 2.28% | 23314 | 0.20% | 0.07% | 2.06% |
| 9/30/18 | **11.62** | 0.16 | 1.01 | 1.17 | (0.43) | (0.11) | (0.54) | **12.25** | 10.36% | 17151 | 0.21% | 0.08% | 1.34% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.14** | $0.32 | $(2.21) | $(1.89) | $(0.40) | $(0.98) | $(1.38) | **$8.87** | (17.91%) | $3301 | 0.25% | 0.19% | 2.90% |
| 9/30/21 | **10.29** | 0.15 | 2.26 | 2.41 | (0.22) | (0.34) | (0.56) | **12.14** | 23.96% | 7435 | 0.26% | 0.18% | 1.32% |
| 9/30/20 | **10.60** | 0.15 | 0.86 | 1.01 | (0.18) | (1.14) | (1.32) | **10.29** | 9.71% | 6025 | 0.28% | 0.17% | 1.54% |
| 9/30/19 | **12.25** | 0.19 | (0.25) | (0.06) | (0.33) | (1.26) | (1.59) | **10.60** | 2.21% | 5024 | 0.30% | 0.17% | 1.83% |
| 9/30/18 | **11.62** | 0.23 | 0.93 | 1.16 | (0.42) | (0.11) | (0.53) | **12.25** | 10.26% | 5780 | 0.31% | 0.19% | 1.96% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.16** | $0.20 | $(2.11) | $(1.91) | $(0.39) | $(0.98) | $(1.37) | **$8.88** | (18.04%) | $12945 | 0.35% | 0.29% | 1.85% |
| 9/30/21 | **10.31** | 0.13 | 2.27 | 2.40 | (0.21) | (0.34) | (0.55) | **12.16** | 23.83% | 15973 | 0.36% | 0.28% | 1.13% |
| 9/30/20 | **10.61** | 0.05 | 0.95 | 1.00 | (0.16) | (1.14) | (1.30) | **10.31** | 9.64% | 11041 | 0.38% | 0.27% | 0.51% |
| 9/30/19 | **12.27** | 0.19 | (0.27) | (0.08) | (0.32) | (1.26) | (1.58) | **10.61** | 2.01% | 3115 | 0.40% | 0.27% | 1.84% |
| 9/30/18 | **11.63** | 0.11 | 1.05 | 1.16 | (0.41) | (0.11) | (0.52) | **12.27** | 10.22% | 2834 | 0.41% | 0.28% | 0.94% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.15** | $0.18 | $(2.10) | $(1.92) | $(0.37) | $(0.98) | $(1.35) | **$8.88** | (18.10%) | $17296 | 0.45% | 0.39% | 1.69% |
| 9/30/21 | **10.29** | 0.14 | 2.25 | 2.39 | (0.19) | (0.34) | (0.53) | **12.15** | 23.77% | 23648 | 0.46% | 0.38% | 1.23% |
| 9/30/20 | **10.59** | 0.14 | 0.84 | 0.98 | (0.14) | (1.14) | (1.28) | **10.29** | 9.49% | 23105 | 0.48% | 0.37% | 1.38% |
| 9/30/19 | **12.25** | 0.20 | (0.30) | (0.10) | (0.30) | (1.26) | (1.56) | **10.59** | 1.88% | 31091 | 0.50% | 0.37% | 1.91% |
| 9/30/18 | **11.62** | 0.18 | 0.96 | 1.14 | (0.40) | (0.11) | (0.51) | **12.25** | 10.05% | 36154 | 0.51% | 0.39% | 1.50% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.96** | $0.16 | $(2.05) | $(1.89) | $(0.36) | $(0.98) | $(1.34) | **$8.73** | (18.17%) | $12041 | 0.60% | 0.54% | 1.48% |
| 9/30/21 | **10.14** | 0.11 | 2.22 | 2.33 | (0.17) | (0.34) | (0.51) | **11.96** | 23.47% | 14161 | 0.61% | 0.53% | 0.98% |
| 9/30/20 | **10.46** | 0.15 | 0.81 | 0.96 | (0.14) | (1.14) | (1.28) | **10.14** | 9.37% | 13465 | 0.63% | 0.52% | 1.51% |
| 9/30/19 | **12.12** | 0.18 | (0.29) | (0.11) | (0.29) | (1.26) | (1.55) | **10.46** | 1.73% | 17701 | 0.65% | 0.52% | 1.71% |
| 9/30/18 | **11.51** | 0.15 | 0.96 | 1.11 | (0.39) | (0.11) | (0.50) | **12.12** | 9.86% | 16469 | 0.66% | 0.54% | 1.26% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.13** | $0.17 | $(2.11) | $(1.94) | $(0.34) | $(0.98) | $(1.32) | **$8.87** | (18.30%) | $20773 | 0.70% | 0.64% | 1.61% |
| 9/30/21 | **10.27** | 0.10 | 2.26 | 2.36 | (0.16) | (0.34) | (0.50) | **12.13** | 23.49% | 32829 | 0.71% | 0.63% | 0.88% |
| 9/30/20 | **10.58** | 0.11 | 0.85 | 0.96 | (0.13) | (1.14) | (1.27) | **10.27** | 9.19% | 31252 | 0.73% | 0.62% | 1.11% |
| 9/30/19 | **12.22** | 0.18 | (0.29) | (0.11) | (0.27) | (1.26) | (1.53) | **10.58** | 1.66% | 30795 | 0.75% | 0.62% | 1.69% |
| 9/30/18 | **11.59** | 0.17 | 0.94 | 1.11 | (0.37) | (0.11) | (0.48) | **12.22** | 9.77% | 34466 | 0.75% | 0.64% | 1.46% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.88** | $0.13 | $(2.04) | $(1.91) | $(0.32) | $(0.98) | $(1.30) | **$8.67** | (18.38%) | $14153 | 0.85% | 0.79% | 1.27% |
| 9/30/21 | **10.08** | 0.10 | 2.20 | 2.30 | (0.16) | (0.34) | (0.50) | **11.88** | 23.30% | 19120 | 0.86% | 0.78% | 0.86% |
| 9/30/20 | **10.44** | 0.10 | 0.82 | 0.92 | (0.14) | (1.14) | (1.28) | **10.08** | 8.98% | 17928 | 0.88% | 0.77% | 1.08% |
| 9/30/19 | **12.08** | 0.14 | (0.26) | (0.12) | (0.26) | (1.26) | (1.52) | **10.44** | 1.58% | 9013 | 0.90% | 0.77% | 1.36% |
| 9/30/18 | **11.47** | 0.12 | 0.96 | 1.08 | (0.36) | (0.11) | (0.47) | **12.08** | 9.63% | 8381 | 0.91% | 0.79% | 1.04% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 28% | 29% | 62% | 38% | 64% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 232 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN IN RETIREMENT FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.78** | $0.33 | $(2.12) | $(1.79) | $(0.42) | $(1.16) | $(1.58) | **$9.41** | (16.12%) | $14100 | 0.22% | 0.06% | 2.97% |
| 9/30/21 | **12.02** | 0.34 | 1.16 | 1.50 | (0.44) | (0.30) | (0.74) | **12.78** | 12.84% | 17522 | 0.14% | 0.06% | 2.69% |
| 9/30/20 | **11.78** | 0.29 | 0.33 | 0.62 | (0.28) | (0.10) | (0.38) | **12.02** | 5.27% | 19693 | 0.12% | 0.06% | 2.52% |
| 9/30/19 | **11.69** | 0.12 | 0.52 | 0.64 | (0.40) | (0.15) | (0.55) | **11.78** | 6.08% | 16125 | 0.22% | 0.06% | 1.08% |
| 9/30/18 | **11.55** | 0.32 | 0.05 | 0.37 | (0.23) |  | (0.23) | **11.69** | 3.22% | 2436 | 0.30% | 0.07% | 2.77% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.81** | $0.32 | $(2.12) | $(1.80) | $(0.41) | $(1.16) | $(1.57) | **$9.44** | (16.20%) | $3826 | 0.32% | 0.16% | 2.91% |
| 9/30/21 | **12.05** | 0.27 | 1.22 | 1.49 | (0.43) | (0.30) | (0.73) | **12.81** | 12.68% | 6568 | 0.24% | 0.16% | 2.14% |
| 9/30/20 | **11.80** | 0.37 | 0.25 | 0.62 | (0.27) | (0.10) | (0.37) | **12.05** | 5.26% | 5758 | 0.22% | 0.16% | 3.16% |
| 9/30/19 | **11.69** | 0.12 | 0.51 | 0.63 | (0.37) | (0.15) | (0.52) | **11.80** | 6.02% | 8776 | 0.32% | 0.16% | 1.01% |
| 9/30/18 | **11.56** | 0.31 | 0.04 | 0.35 | (0.22) |  | (0.22) | **11.69** | 3.02% | 1270 | 0.39% | 0.17% | 2.66% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.82** | $0.35 | $(2.16) | $(1.81) | $(0.40) | $(1.16) | $(1.56) | **$9.45** | (16.26%) | $5973 | 0.42% | 0.26% | 3.10% |
| 9/30/21 | **12.06** | 0.40 | 1.08 | 1.48 | (0.42) | (0.30) | (0.72) | **12.82** | 12.58% | 10332 | 0.34% | 0.26% | 3.18% |
| 9/30/20 | **11.81** | 0.28 | 0.32 | 0.60 | (0.25) | (0.10) | (0.35) | **12.06** | 5.13% | 16755 | 0.32% | 0.26% | 2.39% |
| 9/30/19 | **11.71** | 0.28 | 0.34 | 0.62 | (0.37) | (0.15) | (0.52) | **11.81** | 5.89% | 15324 | 0.42% | 0.26% | 2.44% |
| 9/30/18 | **11.57** | 0.28 | 0.06 | 0.34 | (0.20) |  | (0.20) | **11.71** | 3.00% | 12630 | 0.50% | 0.27% | 2.40% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.82** | $0.31 | $(2.15) | $(1.84) | $(0.38) | $(1.16) | $(1.54) | **$9.44** | (16.45%) | $22751 | 0.52% | 0.36% | 2.82% |
| 9/30/21 | **12.05** | 0.25 | 1.22 | 1.47 | (0.40) | (0.30) | (0.70) | **12.82** | 12.54% | 32436 | 0.44% | 0.36% | 1.99% |
| 9/30/20 | **11.81** | 0.31 | 0.27 | 0.58 | (0.24) | (0.10) | (0.34) | **12.05** | 4.95% | 30972 | 0.42% | 0.36% | 2.69% |
| 9/30/19 | **11.71** | 0.23 | 0.38 | 0.61 | (0.36) | (0.15) | (0.51) | **11.81** | 5.79% | 39483 | 0.52% | 0.36% | 1.97% |
| 9/30/18 | **11.56** | 0.27 | 0.07 | 0.34 | (0.19) |  | (0.19) | **11.71** | 2.97% | 22101 | 0.60% | 0.37% | 2.35% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.60** | $0.27 | $(2.08) | $(1.81) | $(0.36) | $(1.16) | $(1.52) | **$9.27** | (16.47%) | $9504 | 0.67% | 0.51% | 2.48% |
| 9/30/21 | **11.86** | 0.26 | 1.16 | 1.42 | (0.38) | (0.30) | (0.68) | **12.60** | 12.27% | 11952 | 0.59% | 0.51% | 2.08% |
| 9/30/20 | **11.62** | 0.34 | 0.23 | 0.57 | (0.23) | (0.10) | (0.33) | **11.86** | 4.90% | 14384 | 0.57% | 0.51% | 2.93% |
| 9/30/19 | **11.53** | 0.06 | 0.52 | 0.58 | (0.34) | (0.15) | (0.49) | **11.62** | 5.55% | 24032 | 0.67% | 0.51% | 0.52% |
| 9/30/18 | **11.39** | 0.25 | 0.06 | 0.31 | (0.17) |  | (0.17) | **11.53** | 2.75% | 4368 | 0.75% | 0.52% | 2.22% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.65** | $0.29 | $(2.15) | $(1.86) | $(0.21) | $(1.16) | $(1.37) | **$9.42** | (16.64%) | $10307 | 0.77% | 0.61% | 2.59% |
| 9/30/21 | **11.91** | 0.30 | 1.12 | 1.42 | (0.38) | (0.30) | (0.68) | **12.65** | 12.20% | 14697 | 0.69% | 0.61% | 2.45% |
| 9/30/20 | **11.68** | 0.23 | 0.32 | 0.55 | (0.22) | (0.10) | (0.32) | **11.91** | 4.74% | 74154 | 0.67% | 0.61% | 2.02% |
| 9/30/19 | **11.61** | 0.17 | 0.40 | 0.57 | (0.35) | (0.15) | (0.50) | **11.68** | 5.47% | 63336 | 0.77% | 0.61% | 1.53% |
| 9/30/18 | **11.47** | 0.26 | 0.04 | 0.30 | (0.16) |  | (0.16) | **11.61** | 2.67% | 20199 | 0.84% | 0.62% | 2.29% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.48** | $0.26 | $(2.08) | $(1.82) | $(0.32) | $(1.16) | $(1.48) | **$9.18** | (16.67%) | $16575 | 0.92% | 0.76% | 2.36% |
| 9/30/21 | **11.76** | 0.24 | 1.13 | 1.37 | (0.35) | (0.30) | (0.65) | **12.48** | 11.95% | 23241 | 0.84% | 0.76% | 1.94% |
| 9/30/20 | **11.52** | 0.25 | 0.28 | 0.53 | (0.19) | (0.10) | (0.29) | **11.76** | 4.62% | 28918 | 0.82% | 0.76% | 2.23% |
| 9/30/19 | **11.43** | 0.10 | 0.45 | 0.55 | (0.31) | (0.15) | (0.46) | **11.52** | 5.35% | 37510 | 0.92% | 0.76% | 0.88% |
| 9/30/18 | **11.30** | 0.22 | 0.06 | 0.28 | (0.15) |  | (0.15) | **11.43** | 2.45% | 13161 | 1.00% | 0.77% | 1.92% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 58% | 28% | 74% | 39% | 80% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 233 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2020 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.37** | $0.35 | $(2.25) | $(1.90) | $(0.44) | $(1.01) | $(1.45) | **$10.02** | (16.09%) | $37478 | 0.11% | 0.04% | 3.03% |
| 9/30/21 | **12.46** | 0.30 | 1.31 | 1.61 | (0.45) | (0.25) | (0.70) | **13.37** | 13.31% | 51145 | 0.09% | 0.04% | 2.25% |
| 9/30/20 | **12.53** | 0.31 | 0.39 | 0.70 | (0.36) | (0.41) | (0.77) | **12.46** | 5.74% | 43646 | 0.07% | 0.04% | 2.58% |
| 9/30/19 | **13.32** | 0.36 | 0.20 | 0.56 | (0.39) | (0.96) | (1.35) | **12.53** | 5.63% | 35602 | 0.08% | 0.04% | 2.95% |
| 9/30/18 | **13.01** | 0.32 | 0.42 | 0.74 | (0.42) | (0.01) | (0.43) | **13.32** | 5.77% | 19424 | 0.06% | 0.05% | 2.41% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.34** | $0.35 | $(2.26) | $(1.91) | $(0.43) | $(1.01) | $(1.44) | **$9.99** | (16.24%) | $23950 | 0.21% | 0.14% | 2.98% |
| 9/30/21 | **12.43** | 0.32 | 1.28 | 1.60 | (0.44) | (0.25) | (0.69) | **13.34** | 13.22% | 39112 | 0.19% | 0.14% | 2.47% |
| 9/30/20 | **12.51** | 0.35 | 0.33 | 0.68 | (0.35) | (0.41) | (0.76) | **12.43** | 5.57% | 44058 | 0.17% | 0.14% | 2.91% |
| 9/30/19 | **13.30** | 0.30 | 0.25 | 0.55 | (0.38) | (0.96) | (1.34) | **12.51** | 5.56% | 60303 | 0.18% | 0.14% | 2.45% |
| 9/30/18 | **12.99** | 0.32 | 0.41 | 0.73 | (0.41) | (0.01) | (0.42) | **13.30** | 5.69% | 13848 | 0.16% | 0.15% | 2.48% |
| **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.43** | $0.46 | $(2.40) | $(1.94) | $(0.41) | $(1.01) | $(1.42) | **$10.07** | (16.29%) | $9053 | 0.31% | 0.24% | 3.81% |
| 9/30/21 | **12.51** | 0.32 | 1.28 | 1.60 | (0.43) | (0.25) | (0.68) | **13.43** | 13.11% | 29244 | 0.29% | 0.24% | 2.40% |
| 9/30/20 | **12.58** | 0.28 | 0.40 | 0.68 | (0.34) | (0.41) | (0.75) | **12.51** | 5.49% | 35285 | 0.27% | 0.24% | 2.33% |
| 9/30/19 | **13.34** | 0.40 | 0.14 | 0.54 | (0.34) | (0.96) | (1.30) | **12.58** | 5.42% | 31848 | 0.28% | 0.24% | 3.22% |
| 9/30/18 | **13.03** | 0.28 | 0.43 | 0.71 | (0.39) | (0.01) | (0.40) | **13.34** | 5.50% | 83925 | 0.26% | 0.25% | 2.14% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.38** | $0.33 | $(2.28) | $(1.95) | $(0.39) | $(1.01) | $(1.40) | **$10.03** | (16.43%) | $19966 | 0.41% | 0.34% | 2.82% |
| 9/30/21 | **12.46** | 0.28 | 1.30 | 1.58 | (0.41) | (0.25) | (0.66) | **13.38** | 13.02% | 42876 | 0.39% | 0.34% | 2.17% |
| 9/30/20 | **12.53** | 0.35 | 0.31 | 0.66 | (0.32) | (0.41) | (0.73) | **12.46** | 5.40% | 46758 | 0.37% | 0.34% | 2.84% |
| 9/30/19 | **13.30** | 0.34 | 0.19 | 0.53 | (0.34) | (0.96) | (1.30) | **12.53** | 5.38% | 74837 | 0.38% | 0.34% | 2.79% |
| 9/30/18 | **12.99** | 0.29 | 0.40 | 0.69 | (0.37) | (0.01) | (0.38) | **13.30** | 5.43% | 86230 | 0.36% | 0.35% | 2.24% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.06** | $0.30 | $(2.21) | $(1.91) | $(0.37) | $(1.01) | $(1.38) | **$9.77** | (16.51%) | $15666 | 0.56% | 0.49% | 2.63% |
| 9/30/21 | **12.17** | 0.26 | 1.27 | 1.53 | (0.39) | (0.25) | (0.64) | **13.06** | 12.89% | 23718 | 0.54% | 0.49% | 2.05% |
| 9/30/20 | **12.26** | 0.36 | 0.27 | 0.63 | (0.31) | (0.41) | (0.72) | **12.17** | 5.23% | 29367 | 0.52% | 0.49% | 2.98% |
| 9/30/19 | **13.04** | 0.31 | 0.19 | 0.50 | (0.32) | (0.96) | (1.28) | **12.26** | 5.21% | 50600 | 0.53% | 0.49% | 2.60% |
| 9/30/18 | **12.76** | 0.24 | 0.41 | 0.65 | (0.36) | (0.01) | (0.37) | **13.04** | 5.18% | 57866 | 0.51% | 0.50% | 1.90% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.24** | $0.31 | $(2.27) | $(1.96) | $(0.30) | $(1.01) | $(1.31) | **$9.97** | (16.60%) | $20470 | 0.66% | 0.59% | 2.62% |
| 9/30/21 | **12.35** | 0.30 | 1.23 | 1.53 | (0.39) | (0.25) | (0.64) | **13.24** | 12.69% | 31861 | 0.64% | 0.59% | 2.35% |
| 9/30/20 | **12.44** | 0.24 | 0.38 | 0.62 | (0.30) | (0.41) | (0.71) | **12.35** | 5.10% | 88011 | 0.62% | 0.59% | 2.04% |
| 9/30/19 | **13.22** | 0.27 | 0.22 | 0.49 | (0.31) | (0.96) | (1.27) | **12.44** | 5.05% | 73800 | 0.63% | 0.59% | 2.19% |
| 9/30/18 | **12.91** | 0.23 | 0.43 | 0.66 | (0.34) | (0.01) | (0.35) | **13.22** | 5.15% | 76268 | 0.61% | 0.60% | 1.72% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.81** | $0.27 | $(2.16) | $(1.89) | $(0.35) | $(1.01) | $(1.36) | **$9.56** | (16.70%) | $35009 | 0.81% | 0.74% | 2.43% |
| 9/30/21 | **11.96** | 0.23 | 1.24 | 1.47 | (0.37) | (0.25) | (0.62) | **12.81** | 12.57% | 49554 | 0.79% | 0.74% | 1.85% |
| 9/30/20 | **12.05** | 0.25 | 0.34 | 0.59 | (0.27) | (0.41) | (0.68) | **11.96** | 4.97% | 57238 | 0.77% | 0.74% | 2.14% |
| 9/30/19 | **12.84** | 0.28 | 0.18 | 0.46 | (0.29) | (0.96) | (1.25) | **12.05** | 4.93% | 66638 | 0.78% | 0.74% | 2.37% |
| 9/30/18 | **12.56** | 0.22 | 0.40 | 0.62 | (0.33) | (0.01) | (0.34) | **12.84** | 4.98% | 77690 | 0.76% | 0.75% | 1.71% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 52% | 30% | 69% | 46% | 62% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 234 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2025 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.47** | $0.34 | $(2.35) | $(2.01) | $(0.46) | $(1.20) | $(1.66) | **$9.80** | (17.29%) | $44023 | 0.13% | 0.01% | 2.91% |
| 9/30/21 | **12.23** | 0.28 | 1.77 | 2.05 | (0.43) | (0.38) | (0.81) | **13.47** | 17.23% | 56362 | 0.10% | 0.01% | 2.16% |
| 9/30/20 | **12.50** | 0.31 | 0.42 | 0.73 | (0.32) | (0.68) | (1.00) | **12.23** | 6.02% | 49478 | 0.09% | 0.01% | 2.59% |
| 9/30/19 | **13.49** | 0.33 | 0.15 | 0.48 | (0.40) | (1.07) | (1.47) | **12.50** | 5.30% | 40806 | 0.10% | 0.01% | 2.74% |
| 9/30/18 | **13.29** | 0.30 | 0.63 | 0.93 | (0.49) | (0.24) | (0.73) | **13.49** | 7.15% | 21942 | 0.09% | 0.03% | 2.28% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.61** | $0.33 | $(2.39) | $(2.06) | $(0.44) | $(1.20) | $(1.64) | **$9.91** | (17.42%) | $1186 | 0.23% | 0.11% | 2.81% |
| 9/30/21 | **12.35** | 0.16 | 1.90 | 2.06 | (0.42) | (0.38) | (0.80) | **13.61** | 17.13% | 1376 | 0.20% | 0.11% | 1.21% |
| 9/30/20 | **12.62** | 0.28 | 0.44 | 0.72 | (0.31) | (0.68) | (0.99) | **12.35** | 5.87% | 468 | 0.19% | 0.11% | 2.32% |
| 9/30/19 | **13.51** | 0.07 | 0.42 | 0.49 | (0.31) | (1.07) | (1.38) | **12.62** | 5.26% | 527 | 0.20% | 0.11% | 0.61% |
| 9/30/18 | **13.29** | 0.23 | 0.70 | 0.93 | (0.47) | (0.24) | (0.71) | **13.51** | 7.16% | 44 | 0.19% | 0.12% | 1.72% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.49** | $0.42 | $(2.46) | $(2.04) | $(0.43) | $(1.20) | $(1.63) | **$9.82** | (17.48%) | $3811 | 0.32% | 0.21% | 3.50% |
| 9/30/21 | **12.25** | 0.27 | 1.76 | 2.03 | (0.41) | (0.38) | (0.79) | **13.49** | 16.97% | 8867 | 0.30% | 0.21% | 2.04% |
| 9/30/20 | **12.52** | 0.28 | 0.42 | 0.70 | (0.29) | (0.68) | (0.97) | **12.25** | 5.76% | 9970 | 0.29% | 0.21% | 2.37% |
| 9/30/19 | **13.49** | 0.39 | 0.08 | 0.47 | (0.37) | (1.07) | (1.44) | **12.52** | 5.14% | 9278 | 0.30% | 0.21% | 3.23% |
| 9/30/18 | **13.29** | 0.27 | 0.63 | 0.90 | (0.46) | (0.24) | (0.70) | **13.49** | 6.94% | 19582 | 0.29% | 0.23% | 2.00% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.42** | $0.32 | $(2.36) | $(2.04) | $(0.41) | $(1.20) | $(1.61) | **$9.77** | (17.50%) | $24363 | 0.43% | 0.31% | 2.73% |
| 9/30/21 | **12.19** | 0.28 | 1.72 | 2.00 | (0.39) | (0.38) | (0.77) | **13.42** | 16.86% | 34778 | 0.40% | 0.31% | 2.12% |
| 9/30/20 | **12.47** | 0.27 | 0.42 | 0.69 | (0.29) | (0.68) | (0.97) | **12.19** | 5.64% | 39673 | 0.39% | 0.31% | 2.30% |
| 9/30/19 | **13.44** | 0.32 | 0.14 | 0.46 | (0.36) | (1.07) | (1.43) | **12.47** | 5.07% | 43407 | 0.40% | 0.31% | 2.61% |
| 9/30/18 | **13.25** | 0.26 | 0.62 | 0.88 | (0.45) | (0.24) | (0.69) | **13.44** | 6.79% | 47433 | 0.39% | 0.33% | 1.94% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.20** | $0.28 | $(2.30) | $(2.02) | $(0.39) | $(1.20) | $(1.59) | **$9.59** | (17.65%) | $21218 | 0.58% | 0.46% | 2.47% |
| 9/30/21 | **12.00** | 0.25 | 1.70 | 1.95 | (0.37) | (0.38) | (0.75) | **13.20** | 16.65% | 29432 | 0.55% | 0.46% | 1.90% |
| 9/30/20 | **12.29** | 0.36 | 0.30 | 0.66 | (0.27) | (0.68) | (0.95) | **12.00** | 5.49% | 30218 | 0.54% | 0.46% | 3.02% |
| 9/30/19 | **13.27** | 0.30 | 0.13 | 0.43 | (0.34) | (1.07) | (1.41) | **12.29** | 4.88% | 58761 | 0.55% | 0.46% | 2.50% |
| 9/30/18 | **13.09** | 0.22 | 0.63 | 0.85 | (0.43) | (0.24) | (0.67) | **13.27** | 6.66% | 66329 | 0.54% | 0.48% | 1.70% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.25** | $0.29 | $(2.37) | $(2.08) | $(0.20) | $(1.20) | $(1.40) | **$9.77** | (17.74%) | $8655 | 0.68% | 0.56% | 2.48% |
| 9/30/21 | **12.05** | 0.30 | 1.65 | 1.95 | (0.37) | (0.38) | (0.75) | **13.25** | 16.60% | 13796 | 0.65% | 0.56% | 2.33% |
| 9/30/20 | **12.34** | 0.22 | 0.44 | 0.66 | (0.27) | (0.68) | (0.95) | **12.05** | 5.46% | 69042 | 0.64% | 0.56% | 1.89% |
| 9/30/19 | **13.32** | 0.21 | 0.21 | 0.42 | (0.33) | (1.07) | (1.40) | **12.34** | 4.74% | 53785 | 0.65% | 0.56% | 1.71% |
| 9/30/18 | **13.13** | 0.20 | 0.63 | 0.83 | (0.40) | (0.24) | (0.64) | **13.32** | 6.50% | 40219 | 0.64% | 0.58% | 1.54% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.16** | $0.29 | $(2.33) | $(2.04) | $(0.36) | $(1.20) | $(1.56) | **$9.56** | (17.85%) | $38799 | 0.83% | 0.71% | 2.49% |
| 9/30/21 | **11.97** | 0.21 | 1.70 | 1.91 | (0.34) | (0.38) | (0.72) | **13.16** | 16.35% | 59696 | 0.80% | 0.71% | 1.63% |
| 9/30/20 | **12.25** | 0.24 | 0.39 | 0.63 | (0.23) | (0.68) | (0.91) | **11.97** | 5.27% | 66066 | 0.79% | 0.71% | 2.02% |
| 9/30/19 | **13.23** | 0.26 | 0.14 | 0.40 | (0.31) | (1.07) | (1.38) | **12.25** | 4.59% | 78974 | 0.80% | 0.71% | 2.18% |
| 9/30/18 | **13.04** | 0.20 | 0.63 | 0.83 | (0.40) | (0.24) | (0.64) | **13.23** | 6.47% | 87865 | 0.79% | 0.73% | 1.52% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 54% | 35% | 73% | 47% | 67% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

– 235 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2030 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.80** | $0.32 | $(2.49) | $(2.17) | $(0.45) | $(1.16) | $(1.61) | **$10.02** | (18.08%) | $56717 | 0.07% | 0.04% | 2.68% |
| 9/30/21 | **12.05** | 0.25 | 2.14 | 2.39 | (0.36) | (0.28) | (0.64) | **13.80** | 20.27% | 65036 | 0.06% | 0.04% | 1.88% |
| 9/30/20 | **12.51** | 0.28 | 0.45 | 0.73 | (0.30) | (0.89) | (1.19) | **12.05** | 5.91% | 50325 | 0.06% | 0.04% | 2.41% |
| 9/30/19 | **13.91** | 0.32 | 0.03 | 0.35 | (0.40) | (1.35) | (1.75) | **12.51** | 4.77% | 42529 | 0.06% | 0.04% | 2.64% |
| 9/30/18 | **13.38** | 0.29 | 0.78 | 1.07 | (0.49) | (0.05) | (0.54) | **13.91** | 8.11% | 20448 | 0.05% | 0.04% | 2.09% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.73** | $0.32 | $(2.50) | $(2.18) | $(0.43) | $(1.16) | $(1.59) | **$9.96** | (18.18%) | $68661 | 0.17% | 0.14% | 2.69% |
| 9/30/21 | **11.99** | 0.25 | 2.11 | 2.36 | (0.34) | (0.28) | (0.62) | **13.73** | 20.17% | 79905 | 0.16% | 0.14% | 1.90% |
| 9/30/20 | **12.45** | 0.29 | 0.43 | 0.72 | (0.29) | (0.89) | (1.18) | **11.99** | 5.84% | 72808 | 0.16% | 0.14% | 2.50% |
| 9/30/19 | **13.87** | 0.25 | 0.08 | 0.33 | (0.40) | (1.35) | (1.75) | **12.45** | 4.56% | 88078 | 0.16% | 0.14% | 2.03% |
| 9/30/18 | **13.35** | 0.31 | 0.74 | 1.05 | (0.48) | (0.05) | (0.53) | **13.87** | 7.96% | 11359 | 0.15% | 0.14% | 2.26% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.82** | $0.43 | $(2.63) | $(2.20) | $(0.42) | $(1.16) | $(1.58) | **$10.04** | (18.23%) | $15661 | 0.27% | 0.24% | 3.46% |
| 9/30/21 | **12.06** | 0.27 | 2.10 | 2.37 | (0.33) | (0.28) | (0.61) | **13.82** | 20.11% | 45510 | 0.26% | 0.24% | 2.03% |
| 9/30/20 | **12.52** | 0.24 | 0.47 | 0.71 | (0.28) | (0.89) | (1.17) | **12.06** | 5.67% | 50072 | 0.26% | 0.24% | 2.00% |
| 9/30/19 | **13.90** | 0.36 | (0.03)<sup>aa</sup> | 0.33 | (0.36) | (1.35) | (1.71) | **12.52** | 4.48% | 44334 | 0.26% | 0.24% | 2.88% |
| 9/30/18 | **13.37** | 0.25 | 0.79 | 1.04 | (0.46) | (0.05) | (0.51) | **13.90** | 7.88% | 115828 | 0.25% | 0.24% | 1.87% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.77** | $0.32 | $(2.53) | $(2.21) | $(0.40) | $(1.16) | $(1.56) | **$10.00** | (18.33%) | $48874 | 0.37% | 0.34% | 2.63% |
| 9/30/21 | **12.03** | 0.22 | 2.12 | 2.34 | (0.32) | (0.28) | (0.60) | **13.77** | 19.86% | 76955 | 0.36% | 0.34% | 1.68% |
| 9/30/20 | **12.48** | 0.28 | 0.42 | 0.70 | (0.26) | (0.89) | (1.15) | **12.03** | 5.66% | 70563 | 0.36% | 0.34% | 2.33% |
| 9/30/19 | **13.88** | 0.28 | 0.03 | 0.31 | (0.36) | (1.35) | (1.71) | **12.48** | 4.38% | 106439 | 0.36% | 0.34% | 2.33% |
| 9/30/18 | **13.35** | 0.24 | 0.78 | 1.02 | (0.44) | (0.05) | (0.49) | **13.88** | 7.78% | 104308 | 0.35% | 0.34% | 1.79% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.53** | $0.27 | $(2.46) | $(2.19) | $(0.37) | $(1.16) | $(1.53) | **$9.81** | (18.47%) | $22702 | 0.52% | 0.49% | 2.27% |
| 9/30/21 | **11.82** | 0.20 | 2.08 | 2.28 | (0.29) | (0.28) | (0.57) | **13.53** | 19.74% | 33601 | 0.51% | 0.49% | 1.55% |
| 9/30/20 | **12.29** | 0.29 | 0.38 | 0.67 | (0.25) | (0.89) | (1.14) | **11.82** | 5.42% | 34745 | 0.51% | 0.49% | 2.50% |
| 9/30/19 | **13.69** | 0.27 | 0.02 | 0.29 | (0.34) | (1.35) | (1.69) | **12.29** | 4.23% | 57900 | 0.51% | 0.49% | 2.22% |
| 9/30/18 | **13.18** | 0.21 | 0.78 | 0.99 | (0.43) | (0.05) | (0.48) | **13.69** | 7.62% | 68964 | 0.50% | 0.49% | 1.57% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.64** | $0.27 | $(2.50) | $(2.23) | $(0.31) | $(1.16) | $(1.47) | **$9.94** | (18.55%) | $26417 | 0.62% | 0.59% | 2.27% |
| 9/30/21 | **11.92** | 0.25 | 2.05 | 2.30 | (0.30) | (0.28) | (0.58) | **13.64** | 19.67% | 37483 | 0.61% | 0.59% | 1.88% |
| 9/30/20 | **12.39** | 0.19 | 0.47 | 0.66 | (0.24) | (0.89) | (1.13) | **11.92** | 5.34% | 92603 | 0.61% | 0.59% | 1.66% |
| 9/30/19 | **13.78** | 0.23 | 0.05 | 0.28 | (0.32) | (1.35) | (1.67) | **12.39** | 4.13% | 73893 | 0.61% | 0.59% | 1.92% |
| 9/30/18 | **13.25** | 0.20 | 0.78 | 0.98 | (0.40) | (0.05) | (0.45) | **13.78** | 7.52% | 75440 | 0.60% | 0.59% | 1.44% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.28** | $0.24 | $(2.41) | $(2.17) | $(0.35) | $(1.16) | $(1.51) | **$9.60** | (18.67%) | $70110 | 0.77% | 0.74% | 2.05% |
| 9/30/21 | **11.62** | 0.18 | 2.03 | 2.21 | (0.27) | (0.28) | (0.55) | **13.28** | 19.41% | 87304 | 0.76% | 0.74% | 1.38% |
| 9/30/20 | **12.09** | 0.20 | 0.43 | 0.63 | (0.21) | (0.89) | (1.10) | **11.62** | 5.21% | 89115 | 0.76% | 0.74% | 1.78% |
| 9/30/19 | **13.50** | 0.25 | 0.00<sup>d</sup> | 0.25 | (0.31) | (1.35) | (1.66) | **12.09** | 3.92% | 103094 | 0.76% | 0.74% | 2.08% |
| 9/30/18 | **13.00** | 0.18 | 0.77 | 0.95 | (0.40) | (0.05) | (0.45) | **13.50** | 7.38% | 118905 | 0.75% | 0.74% | 1.35% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 58% | 32% | 70% | 39% | 63% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*d* &nbsp;&nbsp;&nbsp;&nbsp;*Amount is less than $0.005 per share.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 236 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2035 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.28** | $0.31 | $(2.58) | $(2.27) | $(0.50) | $(1.52) | $(2.02) | **$9.99** | (18.91%) | $41191 | 0.13% | 0.05% | 2.56% |
| 9/30/21 | **12.07** | 0.21 | 2.59 | 2.80 | (0.31) | (0.28) | (0.59) | **14.28** | 23.66% | 53885 | 0.12% | 0.05% | 1.54% |
| 9/30/20 | **12.73** | 0.26 | 0.48 | 0.74 | (0.30) | (1.10) | (1.40) | **12.07** | 5.75% | 42470 | 0.12% | 0.05% | 2.23% |
| 9/30/19 | **14.18** | 0.32 | (0.09)<sup>aa</sup> | 0.23 | (0.41) | (1.27) | (1.68) | **12.73** | 3.77% | 33309 | 0.12% | 0.05% | 2.56% |
| 9/30/18 | **13.77** | 0.25 | 0.93 | 1.18 | (0.51) | (0.26) | (0.77) | **14.18** | 8.81% | 21586 | 0.11% | 0.07% | 1.83% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.30** | $0.30 | $(2.59) | $(2.29) | $(0.49) | $(1.52) | $(2.01) | **$10.00** | (19.03%) | $2624 | 0.23% | 0.15% | 2.46% |
| 9/30/21 | **12.09** | 0.18 | 2.61 | 2.79 | (0.30) | (0.28) | (0.58) | **14.30** | 23.52% | 3537 | 0.22% | 0.15% | 1.30% |
| 9/30/20 | **12.75** | 0.23 | 0.50 | 0.73 | (0.29) | (1.10) | (1.39) | **12.09** | 5.67% | 2270 | 0.22% | 0.15% | 1.91% |
| 9/30/19 | **14.16** | 0.05 | 0.17 | 0.22 | (0.36) | (1.27) | (1.63) | **12.75** | 3.68% | 1801 | 0.22% | 0.15% | 0.41% |
| 9/30/18 | **13.75** | 0.43 | 0.73 | 1.16 | (0.49) | (0.26) | (0.75) | **14.16** | 8.68% | 132 | 0.21% | 0.18% | 3.09% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.47** | $0.30 | $(2.63) | $(2.33) | $(0.47) | $(1.52) | $(1.99) | **$10.15** | (19.06%) | $6293 | 0.33% | 0.25% | 2.42% |
| 9/30/21 | **12.23** | 0.20 | 2.60 | 2.80 | (0.28) | (0.28) | (0.56) | **14.47** | 23.36% | 8127 | 0.32% | 0.25% | 1.43% |
| 9/30/20 | **12.87** | 0.23 | 0.50 | 0.73 | (0.27) | (1.10) | (1.37) | **12.23** | 5.60% | 8234 | 0.32% | 0.25% | 1.89% |
| 9/30/19 | **14.30** | 0.33 | (0.12)<sup>aa</sup> | 0.21 | (0.37) | (1.27) | (1.64) | **12.87** | 3.55% | 8093 | 0.32% | 0.25% | 2.62% |
| 9/30/18 | **13.88** | 0.25 | 0.91 | 1.16 | (0.48) | (0.26) | (0.74) | **14.30** | 8.59% | 12908 | 0.31% | 0.27% | 1.78% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.39** | $0.29 | $(2.62) | $(2.33) | $(0.46) | $(1.52) | $(1.98) | **$10.08** | (19.17%) | $20432 | 0.43% | 0.35% | 2.35% |
| 9/30/21 | **12.16** | 0.17 | 2.61 | 2.78 | (0.27) | (0.28) | (0.55) | **14.39** | 23.29% | 32891 | 0.42% | 0.35% | 1.24% |
| 9/30/20 | **12.81** | 0.22 | 0.49 | 0.71 | (0.26) | (1.10) | (1.36) | **12.16** | 5.46% | 28848 | 0.42% | 0.35% | 1.83% |
| 9/30/19 | **14.25** | 0.29 | (0.09)<sup>aa</sup> | 0.20 | (0.37) | (1.27) | (1.64) | **12.81** | 3.44% | 32361 | 0.42% | 0.35% | 2.31% |
| 9/30/18 | **13.83** | 0.23 | 0.92 | 1.15 | (0.47) | (0.26) | (0.73) | **14.25** | 8.53% | 33416 | 0.41% | 0.37% | 1.63% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.16** | $0.25 | $(2.56) | $(2.31) | $(0.43) | $(1.52) | $(1.95) | **$9.90** | (19.29%) | $18897 | 0.58% | 0.50% | 2.02% |
| 9/30/21 | **11.97** | 0.17 | 2.54 | 2.71 | (0.24) | (0.28) | (0.52) | **14.16** | 23.08% | 24087 | 0.57% | 0.50% | 1.22% |
| 9/30/20 | **12.63** | 0.30 | 0.38 | 0.68 | (0.24) | (1.10) | (1.34) | **11.97** | 5.30% | 24244 | 0.57% | 0.50% | 2.47% |
| 9/30/19 | **14.06** | 0.27 | (0.09)<sup>aa</sup> | 0.18 | (0.34) | (1.27) | (1.61) | **12.63** | 3.37% | 49044 | 0.57% | 0.50% | 2.17% |
| 9/30/18 | **13.67** | 0.19 | 0.91 | 1.10 | (0.45) | (0.26) | (0.71) | **14.06** | 8.28% | 56342 | 0.56% | 0.52% | 1.40% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.21** | $0.27 | $(2.62) | $(2.35) | $(0.31) | $(1.52) | $(1.83) | **$10.03** | (19.34%) | $7392 | 0.68% | 0.60% | 2.16% |
| 9/30/21 | **12.03** | 0.19 | 2.52 | 2.71 | (0.25) | (0.28) | (0.53) | **14.21** | 22.92% | 13939 | 0.67% | 0.60% | 1.42% |
| 9/30/20 | **12.69** | 0.17 | 0.51 | 0.68 | (0.24) | (1.10) | (1.34) | **12.03** | 5.26% | 42080 | 0.67% | 0.60% | 1.48% |
| 9/30/19 | **14.12** | 0.22 | (0.05)<sup>aa</sup> | 0.17 | (0.33) | (1.27) | (1.60) | **12.69** | 3.21% | 34479 | 0.67% | 0.60% | 1.74% |
| 9/30/18 | **13.70** | 0.17 | 0.93 | 1.10 | (0.42) | (0.26) | (0.68) | **14.12** | 8.23% | 33548 | 0.66% | 0.62% | 1.25% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.10** | $0.22 | $(2.55) | $(2.33) | $(0.40) | $(1.52) | $(1.92) | **$9.85** | (19.50%) | $41463 | 0.83% | 0.75% | 1.85% |
| 9/30/21 | **11.93** | 0.14 | 2.53 | 2.67 | (0.22) | (0.28) | (0.50) | **14.10** | 22.76% | 53677 | 0.82% | 0.75% | 1.02% |
| 9/30/20 | **12.58** | 0.18 | 0.48 | 0.66 | (0.21) | (1.10) | (1.31) | **11.93** | 5.12% | 54970 | 0.82% | 0.75% | 1.51% |
| 9/30/19 | **14.02** | 0.24 | (0.10)<sup>aa</sup> | 0.14 | (0.31) | (1.27) | (1.58) | **12.58** | 2.99% | 61925 | 0.82% | 0.75% | 1.95% |
| 9/30/18 | **13.62** | 0.17 | 0.90 | 1.07 | (0.41) | (0.26) | (0.67) | **14.02** | 8.08% | 69914 | 0.81% | 0.77% | 1.26% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 63% | 34% | 92% | 50% | 62% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized (loss) and net change in unrealized appreciation (depreciation) on investments due to the timing of the commencement of operations of the share class in relation to fluctuating market values of the investments of the Fund.*  |

---

– 237 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2040 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.28** | $0.27 | $(2.60) | $(2.33) | $(0.49) | $(1.48) | $(1.97) | **$9.98** | (19.31%) | $46252 | 0.09% | 0.04% | 2.25% |
| 9/30/21 | **11.54** | 0.19 | 2.81 | 3.00 | (0.26) |  | (0.26) | **14.28** | 26.26% | 51708 | 0.08% | 0.04% | 1.36% |
| 9/30/20 | **12.19** | 0.23 | 0.47 | 0.70 | (0.27) | (1.08) | (1.35) | **11.54** | 5.59% | 38583 | 0.09% | 0.04% | 2.06% |
| 9/30/19 | **13.81** | 0.28 | (0.16)<sup>aa</sup> | 0.12 | (0.39) | (1.35) | (1.74) | **12.19** | 3.22% | 28872 | 0.09% | 0.04% | 2.32% |
| 9/30/18 | **13.23** | 0.27 | 0.92 | 1.19 | (0.49) | (0.12) | (0.61) | **13.81** | 9.19% | 12676 | 0.08% | 0.05% | 2.00% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.26** | $0.27 | $(2.60) | $(2.33) | $(0.48) | $(1.48) | $(1.96) | **$9.97** | (19.36%) | $47871 | 0.19% | 0.14% | 2.19% |
| 9/30/21 | **11.53** | 0.18 | 2.80 | 2.98 | (0.25) |  | (0.25) | **14.26** | 26.08% | 62894 | 0.18% | 0.14% | 1.35% |
| 9/30/20 | **12.18** | 0.24 | 0.45 | 0.69 | (0.26) | (1.08) | (1.34) | **11.53** | 5.51% | 51048 | 0.19% | 0.14% | 2.15% |
| 9/30/19 | **13.80** | 0.22 | (0.11)<sup>aa</sup> | 0.11 | (0.38) | (1.35) | (1.73) | **12.18** | 3.14% | 63062 | 0.19% | 0.14% | 1.84% |
| 9/30/18 | **13.22** | 0.26 | 0.92 | 1.18 | (0.48) | (0.12) | (0.60) | **13.80** | 9.10% | 10301 | 0.18% | 0.15% | 1.94% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.33** | $0.34 | $(2.71) | $(2.37) | $(0.46) | $(1.48) | $(1.94) | **$10.02** | (19.49%) | $11683 | 0.29% | 0.24% | 2.72% |
| 9/30/21 | **11.58** | 0.18 | 2.81 | 2.99 | (0.24) |  | (0.24) | **14.33** | 26.04% | 27788 | 0.28% | 0.24% | 1.31% |
| 9/30/20 | **12.23** | 0.19 | 0.48 | 0.67 | (0.24) | (1.08) | (1.32) | **11.58** | 5.32% | 25091 | 0.29% | 0.24% | 1.67% |
| 9/30/19 | **13.81** | 0.34 | (0.23)<sup>aa</sup> | 0.11 | (0.34) | (1.35) | (1.69) | **12.23** | 3.08% | 22042 | 0.29% | 0.24% | 2.77% |
| 9/30/18 | **13.23** | 0.23 | 0.93 | 1.16 | (0.46) | (0.12) | (0.58) | **13.81** | 8.95% | 68297 | 0.28% | 0.25% | 1.71% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.24** | $0.27 | $(2.63) | $(2.36) | $(0.45) | $(1.48) | $(1.93) | **$9.95** | (19.56%) | $43754 | 0.39% | 0.34% | 2.22% |
| 9/30/21 | **11.51** | 0.15 | 2.81 | 2.96 | (0.23) |  | (0.23) | **14.24** | 25.89% | 65351 | 0.38% | 0.34% | 1.08% |
| 9/30/20 | **12.17** | 0.23 | 0.42 | 0.65 | (0.23) | (1.08) | (1.31) | **11.51** | 5.18% | 52611 | 0.39% | 0.34% | 1.99% |
| 9/30/19 | **13.77** | 0.26 | (0.16)<sup>aa</sup> | 0.10 | (0.35) | (1.35) | (1.70) | **12.17** | 2.99% | 75729 | 0.39% | 0.34% | 2.20% |
| 9/30/18 | **13.19** | 0.22 | 0.92 | 1.14 | (0.44) | (0.12) | (0.56) | **13.77** | 8.86% | 73290 | 0.38% | 0.35% | 1.66% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.97** | $0.23 | $(2.56) | $(2.33) | $(0.42) | $(1.48) | $(1.90) | **$9.74** | (19.70%) | $15650 | 0.54% | 0.49% | 1.87% |
| 9/30/21 | **11.29** | 0.14 | 2.74 | 2.88 | (0.20) |  | (0.20) | **13.97** | 25.69% | 21449 | 0.53% | 0.49% | 1.07% |
| 9/30/20 | **11.96** | 0.24 | 0.38 | 0.62 | (0.21) | (1.08) | (1.29) | **11.29** | 5.04% | 24740 | 0.54% | 0.49% | 2.15% |
| 9/30/19 | **13.56** | 0.24 | (0.16)<sup>aa</sup> | 0.08 | (0.33) | (1.35) | (1.68) | **11.96** | 2.84% | 43641 | 0.54% | 0.49% | 2.05% |
| 9/30/18 | **13.01** | 0.19 | 0.91 | 1.10 | (0.43) | (0.12) | (0.55) | **13.56** | 8.63% | 46980 | 0.53% | 0.50% | 1.40% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.10** | $0.24 | $(2.62) | $(2.38) | $(0.35) | $(1.48) | $(1.83) | **$9.89** | (19.73%) | $15262 | 0.64% | 0.59% | 1.93% |
| 9/30/21 | **11.41** | 0.15 | 2.74 | 2.89 | (0.20) |  | (0.20) | **14.10** | 25.54% | 25723 | 0.63% | 0.59% | 1.13% |
| 9/30/20 | **12.07** | 0.15 | 0.48 | 0.63 | (0.21) | (1.08) | (1.29) | **11.41** | 5.03% | 49795 | 0.64% | 0.59% | 1.34% |
| 9/30/19 | **13.66** | 0.20 | (0.14)<sup>aa</sup> | 0.06 | (0.30) | (1.35) | (1.65) | **12.07** | 2.68% | 42006 | 0.64% | 0.59% | 1.71% |
| 9/30/18 | **13.09** | 0.18 | 0.92 | 1.10 | (0.41) | (0.12) | (0.53) | **13.66** | 8.54% | 44233 | 0.63% | 0.60% | 1.34% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$13.70** | $0.19 | $(2.50) | $(2.31) | $(0.39) | $(1.48) | $(1.87) | **$9.52** | (19.88%) | $43439 | 0.79% | 0.74% | 1.64% |
| 9/30/21 | **11.09** | 0.11 | 2.68 | 2.79 | (0.18) |  | (0.18) | **13.70** | 25.36% | 52607 | 0.78% | 0.74% | 0.85% |
| 9/30/20 | **11.75** | 0.15 | 0.45 | 0.60 | (0.18) | (1.08) | (1.26) | **11.09** | 4.92% | 54015 | 0.79% | 0.74% | 1.34% |
| 9/30/19 | **13.36** | 0.21 | (0.18)<sup>aa</sup> | 0.03 | (0.29) | (1.35) | (1.64) | **11.75** | 2.48% | 59312 | 0.79% | 0.74% | 1.85% |
| 9/30/18 | **12.82** | 0.16 | 0.90 | 1.06 | (0.40) | (0.12) | (0.52) | **13.36** | 8.44% | 64385 | 0.78% | 0.75% | 1.19% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 61% | 33% | 89% | 40% | 59% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 238 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2045 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.76** | $0.27 | $(2.59) | $(2.32) | $(0.53) | $(1.94) | $(2.47) | **$9.97** | (19.49%) | $26481 | 0.18% | 0.02% | 2.15% |
| 9/30/21 | **11.96** | 0.17 | 3.18 | 3.35 | (0.24) | (0.31) | (0.55) | **14.76** | 28.57% | 30290 | 0.16% | 0.02% | 1.24% |
| 9/30/20 | **12.75** | 0.24 | 0.48 | 0.72 | (0.29) | (1.22) | (1.51) | **11.96** | 5.41% | 21522 | 0.18% | 0.02% | 2.04% |
| 9/30/19 | **14.41** | 0.29 | (0.18)<sup>aa</sup> | 0.11 | (0.39) | (1.38) | (1.77) | **12.75** | 3.08% | 19099 | 0.18% | 0.02% | 2.32% |
| 9/30/18 | **13.88** | 0.21 | 1.06 | 1.27 | (0.51) | (0.23) | (0.74) | **14.41** | 9.38% | 9650 | 0.18% | 0.03% | 1.51% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.76** | $0.25 | $(2.59) | $(2.34) | $(0.51) | $(1.94) | $(2.45) | **$9.97** | (19.57%) | $1199 | 0.28% | 0.12% | 2.01% |
| 9/30/21 | **11.96** | 0.17 | 3.17 | 3.34 | (0.23) | (0.31) | (0.54) | **14.76** | 28.46% | 1327 | 0.26% | 0.12% | 1.17% |
| 9/30/20 | **12.76** | 0.20 | 0.50 | 0.70 | (0.28) | (1.22) | (1.50) | **11.96** | 5.25% | 935 | 0.28% | 0.12% | 1.70% |
| 9/30/19 | **14.41** | 0.12 | (0.02)<sup>aa</sup> | 0.10 | (0.37) | (1.38) | (1.75) | **12.76** | 3.02% | 750 | 0.28% | 0.12% | 0.92% |
| 9/30/18 | **13.88** | 0.33 | 0.92 | 1.25 | (0.49) | (0.23) | (0.72) | **14.41** | 9.24% | 147 | 0.28% | 0.14% | 2.33% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.77** | $0.29 | $(2.66) | $(2.37) | $(0.49) | $(1.94) | $(2.43) | **$9.97** | (19.74%) | $3251 | 0.38% | 0.22% | 2.32% |
| 9/30/21 | **11.97** | 0.16 | 3.17 | 3.33 | (0.22) | (0.31) | (0.53) | **14.77** | 28.30% | 4642 | 0.36% | 0.22% | 1.14% |
| 9/30/20 | **12.75** | 0.20 | 0.48 | 0.68 | (0.24) | (1.22) | (1.46) | **11.97** | 5.15% | 4391 | 0.38% | 0.22% | 1.69% |
| 9/30/19 | **14.39** | 0.32 | (0.23)<sup>aa</sup> | 0.09 | (0.35) | (1.38) | (1.73) | **12.75** | 2.92% | 3874 | 0.38% | 0.22% | 2.58% |
| 9/30/18 | **13.86** | 0.23 | 1.01 | 1.24 | (0.48) | (0.23) | (0.71) | **14.39** | 9.19% | 9964 | 0.38% | 0.24% | 1.66% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.67** | $0.25 | $(2.60) | $(2.35) | $(0.48) | $(1.94) | $(2.42) | **$9.90** | (19.76%) | $17419 | 0.48% | 0.32% | 1.99% |
| 9/30/21 | **11.90** | 0.12 | 3.17 | 3.29 | (0.21) | (0.31) | (0.52) | **14.67** | 28.11% | 26780 | 0.46% | 0.32% | 0.87% |
| 9/30/20 | **12.69** | 0.19 | 0.49 | 0.68 | (0.25) | (1.22) | (1.47) | **11.90** | 5.12% | 19671 | 0.48% | 0.32% | 1.59% |
| 9/30/19 | **14.35** | 0.26 | (0.19)<sup>aa</sup> | 0.07 | (0.35) | (1.38) | (1.73) | **12.69** | 2.72% | 21597 | 0.48% | 0.32% | 2.12% |
| 9/30/18 | **13.82** | 0.22 | 1.01 | 1.23 | (0.47) | (0.23) | (0.70) | **14.35** | 9.12% | 18549 | 0.48% | 0.34% | 1.54% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.42** | $0.20 | $(2.53) | $(2.33) | $(0.45) | $(1.94) | $(2.39) | **$9.70** | (19.92%) | $15864 | 0.63% | 0.47% | 1.67% |
| 9/30/21 | **11.70** | 0.12 | 3.10 | 3.22 | (0.19) | (0.31) | (0.50) | **14.42** | 27.98% | 19388 | 0.61% | 0.47% | 0.90% |
| 9/30/20 | **12.51** | 0.24 | 0.40 | 0.64 | (0.23) | (1.22) | (1.45) | **11.70** | 4.89% | 18225 | 0.63% | 0.47% | 2.04% |
| 9/30/19 | **14.15** | 0.24 | (0.18)<sup>aa</sup> | 0.06 | (0.32) | (1.38) | (1.70) | **12.51** | 2.68% | 29963 | 0.63% | 0.47% | 1.93% |
| 9/30/18 | **13.65** | 0.20 | 0.98 | 1.18 | (0.45) | (0.23) | (0.68) | **14.15** | 8.86% | 30899 | 0.63% | 0.49% | 1.42% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.50** | $0.20 | $(2.58) | $(2.38) | $(0.32) | $(1.94) | $(2.26) | **$9.86** | (19.94%) | $6267 | 0.73% | 0.57% | 1.60% |
| 9/30/21 | **11.77** | 0.14 | 3.09 | 3.23 | (0.19) | (0.31) | (0.50) | **14.50** | 27.88% | 11723 | 0.71% | 0.57% | 1.04% |
| 9/30/20 | **12.58** | 0.14 | 0.49 | 0.63 | (0.22) | (1.22) | (1.44) | **11.77** | 4.79% | 28190 | 0.73% | 0.57% | 1.18% |
| 9/30/19 | **14.22** | 0.20 | (0.15)<sup>aa</sup> | 0.05 | (0.31) | (1.38) | (1.69) | **12.58** | 2.54% | 19901 | 0.73% | 0.57% | 1.61% |
| 9/30/18 | **13.70** | 0.18 | 0.99 | 1.17 | (0.42) | (0.23) | (0.65) | **14.22** | 8.77% | 19675 | 0.74% | 0.59% | 1.25% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$14.36** | 0.18 | $(2.53) | $(2.35) | $(0.41) | $(1.94) | $(2.35) | **$9.66** | (20.09%) | $30594 | 0.88% | 0.72% | 1.50% |
| 9/30/21 | **11.66** | 0.10 | 3.06 | 3.16 | (0.15) | (0.31) | (0.46) | **14.36** | 27.59% | 40009 | 0.86% | 0.72% | 0.72% |
| 9/30/20 | **12.47** | 0.14 | 0.47 | 0.61 | (0.20) | (1.22) | (1.42) | **11.66** | 4.62% | 42710 | 0.88% | 0.72% | 1.25% |
| 9/30/19 | **14.11** | 0.22 | (0.19)<sup>aa</sup> | 0.03 | (0.29) | (1.38) | (1.67) | **12.47** | 2.41% | 46767 | 0.88% | 0.72% | 1.82% |
| 9/30/18 | **13.61** | 0.16 | 0.99 | 1.15 | (0.42) | (0.23) | (0.65) | **14.11** | 8.62% | 49481 | 0.88% | 0.74% | 1.19% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 63% | 34% | 95% | 46% | 58% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 239 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2050 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.46** | $0.19 | $(1.91) | $(1.72) | $(0.36) | $(1.10) | $(1.46) | **$7.28** | (19.60%) | $26439 | 0.12% | 0.02% | 2.08% |
| 9/30/21 | **8.31** | 0.12 | 2.23 | 2.35 | (0.17) | (0.03) | (0.20) | **10.46** | 28.53% | 26674 | 0.12% | 0.02% | 1.21% |
| 9/30/20 | **8.80** | 0.16 | 0.33 | 0.49 | (0.19) | (0.79) | (0.98) | **8.31** | 5.29% | 18528 | 0.13% | 0.02% | 2.02% |
| 9/30/19 | **10.18** | 0.20 | (0.15)<sup>aa</sup> | 0.05 | (0.28) | (1.15) | (1.43) | **8.80** | 3.10% | 15050 | 0.14% | 0.02% | 2.27% |
| 9/30/18 | **9.77** | 0.18 | 0.77 | 0.95 | (0.36) | (0.18) | (0.54) | **10.18** | 10.02% | 5973 | 0.14% | 0.04% | 1.82% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.44** | $0.18 | $(1.91) | $(1.73) | $(0.35) | $(1.10) | $(1.45) | **$7.26** | (19.73%) | $41662 | 0.22% | 0.12% | 2.04% |
| 9/30/21 | **8.29** | 0.13 | 2.21 | 2.34 | (0.16) | (0.03) | (0.19) | **10.44** | 28.49% | 50534 | 0.22% | 0.12% | 1.31% |
| 9/30/20 | **8.78** | 0.16 | 0.32 | 0.48 | (0.18) | (0.79) | (0.97) | **8.29** | 5.20% | 42985 | 0.23% | 0.12% | 1.93% |
| 9/30/19 | **10.16** | 0.17 | (0.13)<sup>aa</sup> | 0.04 | (0.27) | (1.15) | (1.42) | **8.78** | 3.03% | 45022 | 0.24% | 0.12% | 1.94% |
| 9/30/18 | **9.76** | 0.18 | 0.75 | 0.93 | (0.35) | (0.18) | (0.53) | **10.16** | 9.83% | 5701 | 0.24% | 0.14% | 1.78% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.50** | $0.22 | $(1.97) | $(1.75) | $(0.34) | $(1.10) | $(1.44) | **$7.31** | (19.78%) | $4478 | 0.32% | 0.22% | 2.39% |
| 9/30/21 | **8.34** | 0.12 | 2.23 | 2.35 | (0.16) | (0.03) | (0.19) | **10.50** | 28.34% | 12565 | 0.32% | 0.22% | 1.19% |
| 9/30/20 | **8.82** | 0.13 | 0.34 | 0.47 | (0.16) | (0.79) | (0.95) | **8.34** | 5.13% | 10119 | 0.33% | 0.22% | 1.59% |
| 9/30/19 | **10.17** | 0.24 | (0.20)<sup>aa</sup> | 0.04 | (0.24) | (1.15) | (1.39) | **8.82** | 2.92% | 8399 | 0.34% | 0.22% | 2.73% |
| 9/30/18 | **9.76** | 0.15 | 0.78 | 0.93 | (0.34) | (0.18) | (0.52) | **10.17** | 9.81% | 41405 | 0.34% | 0.24% | 1.55% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.45** | $0.18 | $(1.93) | $(1.75) | $(0.33) | $(1.10) | $(1.43) | **$7.27** | (19.88%) | $34706 | 0.42% | 0.32% | 1.95% |
| 9/30/21 | **8.30** | 0.09 | 2.23 | 2.32 | (0.14) | (0.03) | (0.17) | **10.45** | 28.20% | 46558 | 0.42% | 0.32% | 0.91% |
| 9/30/20 | **8.79** | 0.16 | 0.30 | 0.46 | (0.16) | (0.79) | (0.95) | **8.30** | 4.98% | 34367 | 0.43% | 0.32% | 1.97% |
| 9/30/19 | **10.16** | 0.18 | (0.15)<sup>aa</sup> | 0.03 | (0.25) | (1.15) | (1.40) | **8.79** | 2.84% | 52850 | 0.44% | 0.32% | 2.06% |
| 9/30/18 | **9.75** | 0.15 | 0.77 | 0.92 | (0.33) | (0.18) | (0.51) | **10.16** | 9.72% | 44569 | 0.44% | 0.34% | 1.47% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.29** | $0.15 | $(1.88) | $(1.73) | $(0.31) | $(1.10) | $(1.41) | **$7.15** | (19.97%) | $12419 | 0.57% | 0.47% | 1.72% |
| 9/30/21 | **8.18** | 0.08 | 2.19 | 2.27 | (0.13) | (0.03) | (0.16) | **10.29** | 27.93% | 16268 | 0.57% | 0.47% | 0.86% |
| 9/30/20 | **8.68** | 0.16 | 0.28 | 0.44 | (0.15) | (0.79) | (0.94) | **8.18** | 4.78% | 15258 | 0.58% | 0.47% | 1.93% |
| 9/30/19 | **10.05** | 0.16 | (0.15)<sup>aa</sup> | 0.01 | (0.23) | (1.15) | (1.38) | **8.68** | 2.66% | 23206 | 0.59% | 0.47% | 1.91% |
| 9/30/18 | **9.65** | 0.13 | 0.77 | 0.90 | (0.32) | (0.18) | (0.50) | **10.05** | 9.56% | 22706 | 0.59% | 0.49% | 1.37% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.35** | $0.15 | $(1.91) | $(1.76) | $(0.26) | $(1.10) | $(1.36) | **$7.23** | (20.08%) | $8582 | 0.67% | 0.57% | 1.67% |
| 9/30/21 | **8.23** | 0.10 | 2.18 | 2.28 | (0.13) | (0.03) | (0.16) | **10.35** | 27.87% | 14761 | 0.67% | 0.57% | 1.00% |
| 9/30/20 | **8.72** | 0.10 | 0.34 | 0.44 | (0.14) | (0.79) | (0.93) | **8.23** | 4.81% | 26813 | 0.68% | 0.57% | 1.22% |
| 9/30/19 | **10.08** | 0.15 | (0.14)<sup>aa</sup> | 0.01 | (0.22) | (1.15) | (1.37) | **8.72** | 2.54% | 21195 | 0.69% | 0.57% | 1.70% |
| 9/30/18 | **9.68** | 0.12 | 0.76 | 0.88 | (0.30) | (0.18) | (0.48) | **10.08** | 9.34% | 20721 | 0.69% | 0.59% | 1.25% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$10.20** | $0.13 | $(1.87) | $(1.74) | $(0.29) | $(1.10) | $(1.39) | **$7.07** | (20.23%) | $28557 | 0.82% | 0.72% | 1.47% |
| 9/30/21 | **8.11** | 0.07 | 2.16 | 2.23 | (0.11) | (0.03) | (0.14) | **10.20** | 27.70% | 34349 | 0.82% | 0.72% | 0.71% |
| 9/30/20 | **8.60** | 0.10 | 0.32 | 0.42 | (0.12) | (0.79) | (0.91) | **8.11** | 4.59% | 32608 | 0.83% | 0.72% | 1.23% |
| 9/30/19 | **9.96** | 0.16 | (0.16)<sup>aa</sup> | 0.00<sup>d</sup> | (0.21) | (1.15) | (1.36) | **8.60** | 2.44% | 34061 | 0.84% | 0.72% | 1.86% |
| 9/30/18 | **9.57** | 0.11 | 0.76 | 0.87 | (0.30) | (0.18) | (0.48) | **9.96** | 9.28% | 39324 | 0.84% | 0.74% | 1.13% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 60% | 36% | 92% | 40% | 65% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*d* &nbsp;&nbsp;&nbsp;&nbsp;*Amount is less than $0.005 per share.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 240 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2055 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.33** | $0.23 | $(2.26) | $(2.03) | $(0.44) | $(1.27) | $(1.71) | **$8.59** | (19.58%) | $12871 | 0.34% | 0.00% | 2.15% |
| 9/30/21 | **10.15** | 0.14 | 2.67 | 2.81 | (0.21) | (0.42) | (0.63) | **12.33** | 28.46% | 13996 | 0.33% | 0.00% | 1.20% |
| 9/30/20 | **10.73** | 0.21 | 0.40 | 0.61 | (0.23) | (0.96) | (1.19) | **10.15** | 5.43% | 9429 | 0.39% | 0.00% | 2.09% |
| 9/30/19 | **12.04** | 0.24 | (0.13)<sup>aa</sup> | 0.11 | (0.33) | (1.09) | (1.42) | **10.73** | 3.15% | 7761 | 0.41% | 0.00% | 2.31% |
| 9/30/18 | **11.71** | 0.19 | 0.94 | 1.13 | (0.44) | (0.36) | (0.80) | **12.04** | 9.97% | 3804 | 0.49% | 0.02% | 1.61% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.33** | $0.21 | $(2.26) | $(2.05) | $(0.42) | $(1.27) | $(1.69) | **$8.59** | (19.69%) | $877 | 0.44% | 0.10% | 1.97% |
| 9/30/21 | **10.15** | 0.10 | 2.70 | 2.80 | (0.20) | (0.42) | (0.62) | **12.33** | 28.35% | 1523 | 0.43% | 0.10% | 0.79% |
| 9/30/20 | **10.73** | 0.17 | 0.43 | 0.60 | (0.22) | (0.96) | (1.18) | **10.15** | 5.34% | 643 | 0.49% | 0.10% | 1.72% |
| 9/30/19 | **12.04** | 0.17 | (0.08)<sup>aa</sup> | 0.09 | (0.31) | (1.09) | (1.40) | **10.73** | 3.02% | 534 | 0.51% | 0.10% | 1.61% |
| 9/30/18 | **11.71** | 0.15 | 0.96 | 1.11 | (0.42) | (0.36) | (0.78) | **12.04** | 9.84% | 231 | 0.59% | 0.11% | 1.24% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.38** | $0.23 | $(2.31) | $(2.08) | $(0.41) | $(1.27) | $(1.68) | **$8.62** | (19.85%) | $2666 | 0.54% | 0.20% | 2.12% |
| 9/30/21 | **10.18** | 0.13 | 2.68 | 2.81 | (0.19) | (0.42) | (0.61) | **12.38** | 28.34% | 3260 | 0.53% | 0.20% | 1.11% |
| 9/30/20 | **10.75** | 0.18 | 0.40 | 0.58 | (0.19) | (0.96) | (1.15) | **10.18** | 5.15% | 2498 | 0.59% | 0.20% | 1.77% |
| 9/30/19 | **12.05** | 0.28 | (0.19)<sup>aa</sup> | 0.09 | (0.30) | (1.09) | (1.39) | **10.75** | 2.99% | 2291 | 0.61% | 0.20% | 2.63% |
| 9/30/18 | **11.72** | 0.18 | 0.93 | 1.11 | (0.42) | (0.36) | (0.78) | **12.05** | 9.78% | 5512 | 0.69% | 0.22% | 1.55% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.28** | $0.20 | $(2.27) | $(2.07) | $(0.40) | $(1.27) | $(1.67) | **$8.54** | (19.92%) | $8852 | 0.64% | 0.30% | 1.87% |
| 9/30/21 | **10.11** | 0.10 | 2.67 | 2.77 | (0.18) | (0.42) | (0.60) | **12.28** | 28.13% | 10954 | 0.63% | 0.30% | 0.85% |
| 9/30/20 | **10.69** | 0.16 | 0.42 | 0.58 | (0.20) | (0.96) | (1.16) | **10.11** | 5.13% | 7482 | 0.69% | 0.30% | 1.61% |
| 9/30/19 | **12.00** | 0.21 | (0.14)<sup>aa</sup> | 0.07 | (0.29) | (1.09) | (1.38) | **10.69** | 2.79% | 8364 | 0.71% | 0.30% | 1.98% |
| 9/30/18 | **11.67** | 0.18 | 0.92 | 1.10 | (0.41) | (0.36) | (0.77) | **12.00** | 9.73% | 6286 | 0.79% | 0.32% | 1.52% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.20** | $0.19 | $(2.25) | $(2.06) | $(0.38) | $(1.27) | $(1.65) | **$8.49** | (19.98%) | $5976 | 0.79% | 0.45% | 1.76% |
| 9/30/21 | **10.04** | 0.11 | 2.63 | 2.74 | (0.16) | (0.42) | (0.58) | **12.20** | 28.02% | 7822 | 0.78% | 0.45% | 0.92% |
| 9/30/20 | **10.64** | 0.22 | 0.33 | 0.55 | (0.19) | (0.96) | (1.15) | **10.04** | 4.85% | 6887 | 0.84% | 0.45% | 2.20% |
| 9/30/19 | **11.94** | 0.21 | (0.14)<sup>aa</sup> | 0.07 | (0.28) | (1.09) | (1.37) | **10.64** | 2.75% | 12251 | 0.86% | 0.45% | 2.02% |
| 9/30/18 | **11.62** | 0.14 | 0.93 | 1.07 | (0.39) | (0.36) | (0.75) | **11.94** | 9.50% | 11111 | 0.94% | 0.47% | 1.19% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.23** | $0.14 | $(2.26) | $(2.12) | $(0.17) | $(1.27) | $(1.44) | **$8.67** | (19.98%) | $1265 | 0.89% | 0.55% | 1.27% |
| 9/30/21 | **10.08** | 0.11 | 2.62 | 2.73 | (0.16) | (0.42) | (0.58) | **12.23** | 27.80% | 6298 | 0.88% | 0.55% | 0.96% |
| 9/30/20 | **10.67** | 0.13 | 0.42 | 0.55 | (0.18) | (0.96) | (1.14) | **10.08** | 4.83% | 10137 | 0.94% | 0.55% | 1.29% |
| 9/30/19 | **11.97** | 0.16 | (0.11)<sup>aa</sup> | 0.05 | (0.26) | (1.09) | (1.35) | **10.67** | 2.55% | 7587 | 0.96% | 0.55% | 1.57% |
| 9/30/18 | **11.64** | 0.12 | 0.94 | 1.06 | (0.37) | (0.36) | (0.73) | **11.97** | 9.41% | 7070 | 1.04% | 0.57% | 1.02% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.12** | $0.15 | $(2.23) | $(2.08) | $(0.35) | $(1.27) | $(1.62) | **$8.42** | (20.23%) | $20114 | 1.04% | 0.70% | 1.46% |
| 9/30/21 | **9.99** | 0.09 | 2.60 | 2.69 | (0.14) | (0.42) | (0.56) | **12.12** | 27.60% | 23885 | 1.03% | 0.70% | 0.76% |
| 9/30/20 | **10.58** | 0.11 | 0.42 | 0.53 | (0.16) | (0.96) | (1.12) | **9.99** | 4.69% | 24149 | 1.09% | 0.70% | 1.17% |
| 9/30/19 | **11.88** | 0.19 | (0.15)<sup>aa</sup> | 0.04 | (0.25) | (1.09) | (1.34) | **10.58** | 2.44% | 22185 | 1.11% | 0.70% | 1.79% |
| 9/30/18 | **11.57** | 0.13 | 0.90 | 1.03 | (0.36) | (0.36) | (0.72) | **11.88** | 9.22% | 21236 | 1.19% | 0.72% | 1.10% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 64% | 38% | 89% | 50% | 62% |

---

*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

---

| | |
|:---|:---|
| *aa* | &nbsp;&nbsp;&nbsp;&nbsp;*The amount shown for a share outstanding does not correspond with the aggregate net realized and unrealized gain (loss) for the period due to the timing of purchases and redemptions of Fund shares in relation to the fluctuating market values of the Fund.*  |

---

– 241 –

**MASSMUTUAL RETIRESMART<sup>SM</sup> BY JPMORGAN 2060 FUND**

---

| | | | | | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
|  | | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Income (loss) from investment<br> operations** | **Less distributions to shareholders** | **Less distributions to shareholders** | **Less distributions to shareholders** | | | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** | **Ratios / Supplemental Data** |
|  | <br>**Net <br> asset <br> value, <br> beginning <br> of the <br> period** | **Net <br> investment <br> income <br> (loss)<sup>c,j</sup>** | **Net <br> realized <br> and <br> unrealized <br> gain (loss) <br> on <br> investments** | **Total <br> income <br> (loss) from <br> investment <br> operations** | **From net <br> investment <br> income** | **From net <br> realized <br> gains** | **Total <br> distributions** | <br>**Net <br> asset <br> value, <br> end of <br> the <br> period** | <br>**Total <br> return<sup>l,m</sup>** | **Net <br> assets, <br> end of <br> the <br> period <br> (000's)** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> before <br> expense <br> waivers<sup>w</sup>** | **Ratio of <br> expenses <br> to average <br> daily net <br> assets <br> after <br> expense <br> waivers<sup>j</sup>** | **Net <br> investment <br> income <br> (loss) to <br> average <br> daily net <br> assets**  |
| **Class I** | **Class I** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.03** | $0.24 | $(2.27) | $(2.03) | $(0.41) | $(1.05) | $(1.46) | **$8.54** | (19.60%) | $11505 | 0.95% | 0.00% | 2.31% |
| 9/30/21 | **9.91** | 0.15 | 2.59 | 2.74 | (0.20) | (0.42) | (0.62) | **12.03** | 28.43% | 14808 | 1.07% | 0.00% | 1.29% |
| 9/30/20 | **10.53** | 0.20 | 0.39 | 0.59 | (0.23) | (0.98) | (1.21) | **9.91** | 5.39% | 10758 | 1.32% | 0.00% | 2.06% |
| 9/30/19 | **11.92** | 0.28 | (0.19) | 0.09 | (0.32) | (1.16) | (1.48) | **10.53** | 3.15% | 10904 | 1.57% | 0.00% | 2.70% |
| 9/30/18 | **11.40** | 0.22 | 0.89 | 1.11 | (0.39) | (0.20) | (0.59) | **11.92** | 10.03% | 11994 | 1.68% | 0.02% | 1.90% |
| **Class R5** | **Class R5** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$12.00** | $0.22 | $(2.26) | $(2.04) | $(0.37) | $(1.05) | $(1.42) | **$8.54** | (19.72%) | $194 | 1.05% | 0.10% | 2.05% |
| 9/30/21 | **9.89** | 0.13 | 2.59 | 2.72 | (0.19) | (0.42) | (0.61) | **12.00** | 28.27% | 1352 | 1.17% | 0.10% | 1.12% |
| 9/30/20 | **10.51** | 0.25 | 0.33 | 0.58 | (0.22) | (0.98) | (1.20) | **9.89** | 5.33% | 764 | 1.42% | 0.10% | 2.51% |
| 9/30/19 | **11.91** | 0.10 | (0.03) | 0.07 | (0.31) | (1.16) | (1.47) | **10.51** | 2.96% | 1257 | 1.67% | 0.10% | 1.01% |
| 9/30/18 | **11.39** | 0.13 | 0.97 | 1.10 | (0.38) | (0.20) | (0.58) | **11.91** | 9.94% | 319 | 1.78% | 0.11% | 1.09% |
| **Service Class** | **Service Class** | **Service Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.97** | $0.21 | $(2.24) | $(2.03) | $(0.40) | $(1.05) | $(1.45) | **$8.49** | (19.75%) | $1215 | 1.15% | 0.20% | 1.97% |
| 9/30/21 | **9.87** | 0.12 | 2.58 | 2.70 | (0.18) | (0.42) | (0.60) | **11.97** | 28.15% | 2047 | 1.27% | 0.21% | 1.03% |
| 9/30/20 | **10.49** | 0.12 | 0.45 | 0.57 | (0.21) | (0.98) | (1.19) | **9.87** | 5.23% | 1453 | 1.52% | 0.20% | 1.20% |
| 9/30/19 | **11.90** | 0.32 | (0.27) | 0.05 | (0.30) | (1.16) | (1.46) | **10.49** | 2.79% | 529 | 1.77% | 0.20% | 3.10% |
| 9/30/18 | **11.38** | 0.12 | 0.98 | 1.10 | (0.38) | (0.20) | (0.58) | **11.90** | 9.88% | 668 | 1.88% | 0.21% | 1.01% |
| **Administrative Class** | **Administrative Class** | **Administrative Class** |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.95** | $0.19 | $(2.25) | $(2.06) | $(0.38) | $(1.05) | $(1.43) | **$8.46** | (19.96%) | $1788 | 1.25% | 0.30% | 1.81% |
| 9/30/21 | **9.85** | 0.09 | 2.60 | 2.69 | (0.17) | (0.42) | (0.59) | **11.95** | 28.08% | 2210 | 1.37% | 0.33% | 0.79% |
| 9/30/20 | **10.48** | 0.12 | 0.43 | 0.55 | (0.20) | (0.98) | (1.18) | **9.85** | 5.07% | 1304 | 1.62% | 0.30% | 1.29% |
| 9/30/19 | **11.87** | 0.20 | (0.15) | 0.05 | (0.28) | (1.16) | (1.44) | **10.48** | 2.81% | 665 | 1.87% | 0.30% | 1.97% |
| 9/30/18 | **11.36** | 0.17 | 0.91 | 1.08 | (0.37) | (0.20) | (0.57) | **11.87** | 9.71% | 448 | 1.98% | 0.32% | 1.47% |
| **Class R4** | **Class R4** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.94** | $0.18 | $(2.25) | $(2.07) | $(0.36) | $(1.05) | $(1.41) | **$8.46** | (20.02%) | $923 | 1.40% | 0.45% | 1.74% |
| 9/30/21 | **9.85** | 0.11 | 2.57 | 2.68 | (0.17) | (0.42) | (0.59) | **11.94** | 27.90% | 1019 | 1.52% | 0.45% | 0.92% |
| 9/30/20 | **10.47** | 0.12 | 0.42 | 0.54 | (0.18) | (0.98) | (1.16) | **9.85** | 4.97% | 769 | 1.77% | 0.45% | 1.26% |
| 9/30/19 | **11.87** | 0.14 | (0.11) | 0.03 | (0.27) | (1.16) | (1.43) | **10.47** | 2.60% | 374 | 2.02% | 0.45% | 1.36% |
| 9/30/18 | **11.36** | 0.14 | 0.92 | 1.06 | (0.35) | (0.20) | (0.55) | **11.87** | 9.58% | 255 | 2.13% | 0.47% | 1.24% |
| **Class A** | **Class A** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.89** | $0.20 | $(2.28) | $(2.08) | $(0.28) | $(1.05) | $(1.33) | **$8.48** | (20.10%) | $329 | 1.50% | 0.55% | 1.86% |
| 9/30/21 | **9.83** | 0.12 | 2.52 | 2.64 | (0.16) | (0.42) | (0.58) | **11.89** | 27.59% | 613 | 1.62% | 0.59% | 1.04% |
| 9/30/20 | **10.46** | 0.07 | 0.46 | 0.53 | (0.18) | (0.98) | (1.16) | **9.83** | 4.89% | 1190 | 1.87% | 0.55% | 0.74% |
| 9/30/19 | **11.86** | 0.19 | (0.17) | 0.02 | (0.26) | (1.16) | (1.42) | **10.46** | 2.50% | 437 | 2.12% | 0.55% | 1.84% |
| 9/30/18 | **11.35** | 0.10 | 0.95 | 1.05 | (0.34) | (0.20) | (0.54) | **11.86** | 9.47% | 304 | 2.23% | 0.56% | 0.89% |
| **Class R3** | **Class R3** |  |  |  |  |  |  |  |  |  |  |  |  |
| 9/30/22 | **$11.87** | $0.14 | $(2.22) | $(2.08) | $(0.32) | $(1.05) | $(1.37) | **$8.42** | (20.18%) | $1343 | 1.65% | 0.70% | 1.34% |
| 9/30/21 | **9.80** | 0.12 | 2.51 | 2.63 | (0.14) | (0.42) | (0.56) | **11.87** | 27.53% | 1510 | 1.77% | 0.70% | 1.03% |
| 9/30/20 | **10.41** | 0.08 | 0.43 | 0.51 | (0.14) | (0.98) | (1.12) | **9.80** | 4.66% | 1885 | 2.02% | 0.70% | 0.89% |
| 9/30/19 | **11.80** | 0.14 | (0.12) | 0.02 | (0.25) | (1.16) | (1.41) | **10.41** | 2.49% | 1096 | 2.27% | 0.70% | 1.38% |
| 9/30/18 | **11.32** | 0.08 | 0.94 | 1.02 | (0.34) | (0.20) | (0.54) | **11.80** | 9.20% | 800 | 2.38% | 0.72% | 0.73% |

---

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
|  | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** | **Year ended September 30** |
|  | **2022** | **2021** | **2020** | **2019** | **2018** |
| **Portfolio turnover rate**  | 78% | 38% | 77% | 51% | 58% |

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*c* &nbsp;&nbsp;&nbsp;&nbsp;*Per share amount calculated on the average shares method.* 

*j* &nbsp;&nbsp;&nbsp;&nbsp;*Computed after giving effect to an agreement by MML Advisers to waive certain fees and expenses of the Fund.* 

*l* &nbsp;&nbsp;&nbsp;&nbsp;*Employee retirement benefit plans that invest plan assets in the Separate Investment Accounts (SIAs) may be subject to certain charges as set forth in their respective Plan Documents. Total return figures would be lower for the periods presented if they reflected these charges.* 

*m* &nbsp;&nbsp;&nbsp;&nbsp;*Total return excludes sales charges, if any, and would be lower for the period presented if it reflected these charges.* 

*w* &nbsp;&nbsp;&nbsp;&nbsp;*Expenses of the underlying funds are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of the expenses of any underlying fund.* 

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### Index Descriptions
The **Bloomberg U.S. Aggregate Bond Index** measures the performance of investment grade, U.S. dollar-denominated, fixed-rate taxable bond market securities, including Treasuries, government-related and corporate securities, mortgage-backed securities (MBS) (agency fixed-rate and hybrid ARM pass-throughs), asset-backed securities (ABS), and commercial mortgage-backed securities (CMBS). It rolls up into other Bloomberg flagship indexes, such as the multi-currency Global Aggregate Index and the U.S. Universal Index, which includes high yield and emerging markets debt. The Index does not reflect any deduction for fees, expenses, or taxes and cannot be purchased directly by investors.

The **Lipper Balanced Fund Index** is an unmanaged, equally weighted index of the 30 largest mutual funds within the Lipper Balanced Category. The Index does not reflect any deduction for taxes and cannot be purchased directly by investors.

The **S&P 500 Index** measures the performance of 500 widely held stocks in the U.S. equity market. Standard and Poor's chooses member companies for the index based on market size, liquidity, and industry group representation. Included are the stocks of industrial, financial, utility, and transportation companies. Since mid-1989, this composition has been more flexible and the number of issues in each sector has varied. It is market capitalization-weighted. The Index does not reflect any deduction for fees, expenses, or taxes and cannot be purchased directly by investors.

The **S&P Target Date**<sup>®</sup> **Index Series** consists of 13 multi-asset class indexes: the S&P Target Date Retirement Income Index and 12 date-specific indexes, corresponding to a specific target retirement date. Each index provides varying levels of exposure to equities and fixed income. Each target date allocation is created and retired according to a pre-determined schedule related to the respective target date. Each Index does not reflect any deduction for fees, expenses, or taxes and cannot be purchased directly by investors.

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### MassMutual Funds
1295 State Street

Springfield, Massachusetts 01111-0001

#### Learning More About the Funds
You can learn more about the Funds by reading the Funds' **Annual and Semiannual Reports** and the **SAI**. You may obtain free copies of this information from the Funds or from the SEC using one or more of the methods set forth below. In the Annual and Semiannual Reports, you will find a discussion of market conditions and investment strategies that significantly affected each Fund's performance during the period covered by the Report and a listing of each Fund's portfolio securities as of the end of such period. The SAI provides additional information about the Funds and will provide you with more detail regarding the organization and operation of the Funds, including their investment strategies. The SAI is incorporated by reference into this Prospectus and is therefore legally considered a part of this Prospectus.

#### How to Obtain Information

#### From the Funds:
You may request information about the Funds free of charge (including the Annual/Semiannual Reports and the SAI) or make shareholder inquiries by calling 1-888-309-3539 or by writing the Funds, c/o Massachusetts Mutual Life Insurance Company, 1295 State Street, Springfield, Massachusetts 01111-0001, **Attention: Investment Management Solutions.** You may also obtain copies of the Annual/Semiannual Reports and the SAI free of charge at https://www.massmutual.com/funds.

#### From the SEC:
Information about the Funds (including the Annual/Semiannual Reports and the SAI) is available on the SEC's EDGAR database on its Internet site at http://www.sec.gov. You can also get copies of this information, upon payment of a copying fee, by electronic request at publicinfo@sec.gov.

When obtaining information about the Funds from the SEC, you may find it useful to reference the

#### Funds' SEC file number: 811-8274 .

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