# EDGAR Filing Document

**Accession Number:** 0000916053
**File Stem:** 0001133228-26-009361
**Filing Date:** 2026-6
**Character Count:** 2548
**Document Hash:** b246f5a6a79c4d503bb04252f0bfe624
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001133228-26-009361.hdr.sgml**: 20260622

**ACCESSION NUMBER**: 0001133228-26-009361

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260622

**DATE AS OF CHANGE**: 20260622

**EFFECTIVENESS DATE**: 20260622

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MASSMUTUAL SELECT FUNDS
- **CENTRAL INDEX KEY:** 0000916053

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0930

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-73824
- **FILM NUMBER:** 261107346

**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 Mid Cap Growth Fund (Series ID: S000003665)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000240790 | Class Y      | MMNGX           |

#### MASSMUTUAL FUNDS<br>

#### MassMutual Mid Cap Growth Fund<br>

#### Supplement dated June 22, 2026 to the<br>

#### Prospectus dated February 1, 2026 and the<br>

#### Summary Prospectus dated February 1, 2026
This supplement provides new and additional information beyond that contained in the Prospectus and Summary Prospectus, and any previous supplements. It should be retained and read in conjunction with the Prospectus and Summary Prospectus, and any previous supplements.

*The Board of Trustees of the MassMutual Select Funds has approved the termination of Class Y shares of the **MassMutual Mid Cap Growth Fund** (the "Fund"). Effective on or about September 11, 2026 (the "Termination Date"), shareholders of Class Y shares of the Fund will receive proceeds in proportion to the number of Class Y shares held by each of them on the Termination Date.* 

*Effective on and after July 1, 2026, Class Y shares of the Fund will not be available for purchase by new investors. Customers who are invested in Class Y shares of the Fund as of June 30, 2026 will continue to be able to invest through the Termination Date. Exceptions will only be permitted on a case-by-case basis at the discretion of MML Distributors, LLC.* 

#### PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE

#### MCG-26-01<br>

#### SELPRO-26-05