# EDGAR Filing Document

**Accession Number:** 0001469192
**File Stem:** 0001741773-23-000848
**Filing Date:** 2023-3
**Character Count:** 3587
**Document Hash:** 7ef8724edc8b01c6edf104633b1a3054
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001741773-23-000848.hdr.sgml**: 20230303

**ACCESSION NUMBER**: 0001741773-23-000848

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20230303

**DATE AS OF CHANGE**: 20230303

**EFFECTIVENESS DATE**: 20230303

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MAINSTAY FUNDS TRUST
- **CENTRAL INDEX KEY:** 0001469192
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1031

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-160918
- **FILM NUMBER:** 23701748

**BUSINESS ADDRESS:**
- **STREET 1:** 51 MADISON AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10010
- **BUSINESS PHONE:** 212 576 7000

**MAIL ADDRESS:**
- **STREET 1:** 51 MADISON AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10010

## Series and Classes Contracts Data

### MainStay Short Term Bond Fund (Series ID: S000028536)

---

|  |  |  |
|:---|:---|:---|
| Class Name     | Ticker Symbol | Class ID   |
| Class I        | MIXIX         | C000087370 |
| Investor Class | MIXNX         | C000087371 |
| Class A        | MIXAX         | C000087372 |
| SIMPLE Class   | MIXMX         | C000221665 |

---

### MainStay Balanced Fund (Series ID: S000036714)

---

|  |  |  |
|:---|:---|:---|
| Class Name     | Ticker Symbol | Class ID   |
| Class A        | MBNAX         | C000112258 |
| Class B        | MBNBX         | C000112259 |
| Class C        | MBACX         | C000112260 |
| Class I        | MBAIX         | C000112261 |
| Class R1       | MBNRX         | C000112262 |
| Class R2       | MBCRX         | C000112263 |
| Class R3       | MBDRX         | C000112264 |
| Investor Class | MBINX         | C000112265 |
| Class R6       | MBERX         | C000185940 |

---

## Series and Classes Contracts Data

### MainStay Short Term Bond Fund (Series ID: S000028536)

| Class ID   | Class Name     | Ticker Symbol   |
|:---|:---|:---|
| C000087370 | Class I        | MIXIX           |
| C000087371 | Investor Class | MIXNX           |
| C000087372 | Class A        | MIXAX           |
| C000221665 | SIMPLE Class   | MIXMX           |

### MainStay Balanced Fund (Series ID: S000036714)

| Class ID   | Class Name     | Ticker Symbol   |
|:---|:---|:---|
| C000112258 | Class A        | MBNAX           |
| C000112259 | Class B        | MBNBX           |
| C000112260 | Class C        | MBACX           |
| C000112261 | Class I        | MBAIX           |
| C000112262 | Class R1       | MBNRX           |
| C000112263 | Class R2       | MBCRX           |
| C000112264 | Class R3       | MBDRX           |
| C000112265 | Investor Class | MBINX           |
| C000185940 | Class R6       | MBERX           |

#### MAINSTAY FUNDS TRUST

#### MainStay Balanced Fund

#### MainStay Short Term Bond Fund <br> (the "Funds")
Supplement dated March 3, 2023 ("Supplement") to the Summary Prospectuses, Prospectus, and

Statement of Additional Information, each dated February 28, 2023

*Capitalized terms and certain other terms used in this Supplement, unless otherwise defined in this Supplement, have the meanings assigned to them in the Summary Prospectuses, Prospectus and Statement of Additional Information.* 

Effective on or about June 30, 2023, AJ Rzad will no longer serve as a portfolio manager for the Funds. All references to Mr. Rzad will be deleted in their entirety at that time. Except for this change, each Fund's portfolio management team will remain the same.

#### PLEASE RETAIN THIS SUPPLEMENT FOR YOUR FUTURE REFERENCE.

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