# EDGAR Filing Document

**Accession Number:** 0001469192
**File Stem:** 0001741773-23-000549
**Filing Date:** 2023-2
**Character Count:** 31962
**Document Hash:** 23664cee31acba810e9e6e72d2c2af08
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001741773-23-000549.hdr.sgml**: 20230228

**ACCESSION NUMBER**: 0001741773-23-000549

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20230228

**DATE AS OF CHANGE**: 20230228

**EFFECTIVENESS DATE**: 20230228

**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:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-160918
- **FILM NUMBER:** 23678714

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

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;![](img_aab20d099ea14f1.jpg)<br>**MainStay Short Term Bond Fund** | &nbsp;&nbsp;![](img_aab20d099ea14f1.jpg)<br>**MainStay Short Term Bond Fund** | **Summary Prospectus**<br>February 28, 2023  |
| &nbsp;&nbsp;**Class**/Ticker | **A MIXAX Investor MIXNX I MIXIX SIMPLE MIXMX**  | **A MIXAX Investor MIXNX I MIXIX SIMPLE MIXMX**  |

---

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus, reports to shareholders and other information about the Fund by going online to newyorklifeinvestments.com, by calling 800-624-6782 or by sending an e-mail to MainStayShareholderServices@nylim.com. The Fund's Prospectus and Statement of Additional Information, both dated February 28, 2023, as may be amended from time to time, are incorporated by reference into this Summary Prospectus.

**Investment Objective**

The Fund seeks current income consistent with capital preservation.

**Fees and Expenses of the Fund** 

The table below describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. **You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below.** You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $250,000 in the Fund. In addition, different financial intermediary firms and financial professionals may impose different sales loads and waivers. More information about these and other discounts or waivers is available from your financial professional, in the "Information on Sales Charges" section starting on page 152 of the Prospectus and Appendix A – Intermediary-Specific Sales Charge Waivers and Discounts, and in the "Alternative Sales Arrangements" section on page 138 of the Statement of Additional Information.

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| | | | | |
|:---|:---|:---|:---|:---|
|  | **Class A** | **Investor Class** | **Class I** | **SIMPLE Class** |
| **Shareholder Fees** (fees paid directly from your investment) |  |  |  |  |
| Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price) | 1.00 | 0.50 |  |  |
| Maximum Deferred Sales Charge (Load) (as a percentage of the lesser of the original offering price or redemption proceeds) | None<br><sup>1</sup>  | None<br><sup>1</sup>  |  |  |
| **Annual Fund Operating Expenses** (expenses that you pay each year as a percentage of the value of your investment) |  |  |  |  |
| Management Fees (as an annual percentage of the Fund's average daily net assets)<sup>2</sup> | 0.25 | 0.25 | 0.25 | 0.25 |
| Distribution and/or Service (12b-1) Fees | 0.25 | 0.25 |  | 0.50 |
| Other Expenses | 0.38 | 0.82 | 0.35 | 0.48 |
| Total Annual Fund Operating Expenses | 0.88 | 1.32 | 0.60 | 1.23 |
| Waivers / Reimbursements<sup>4</sup> | (0.06 | (0.40 | (0.20 | (0.06 |
| Total Annual Fund Operating Expenses After Waivers / Reimbursements<sup>4</sup> | 0.82 | 0.92 | 0.40 | 1.17 |

---

1. No initial sales charge applies on investments of $250,000 or more (and certain other qualified purchases). However, a contingent deferred sales charge of 0.50% may be imposed on certain redemptions made within 12 months of the date of purchase on shares that were purchased without an initial sales charge.

2. The management fee is as follows: 0.25% on assets up to $1 billion and 0.20% on assets over $1 billion.

3. Restated to reflect the expenses expected to be incurred during the current fiscal year.

4. New York Life Investment Management LLC ("New York Life Investments") has contractually agreed to waive fees and/or reimburse expenses so that Total Annual Fund Operating Expenses (excluding taxes, interest, litigation, extraordinary expenses, brokerage and other transaction expenses relating to the purchase or sale of portfolio investments, and acquired (underlying) fund fees and expenses) do not exceed the following percentages of its average daily net assets: Class A, 0.82%; Investor Class, 0.92%; Class I, 0.40%; and SIMPLE Class, 1.17%. This agreement will remain in effect until February 28, 2024, and shall renew automatically for one-year terms unless New York Life Investments provides written notice of termination prior to the start of the next term or upon approval of the Board of Trustees of the Fund.

**Example**

The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated whether or not you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects the contractual fee waiver and/or expense reimbursement arrangement, if applicable, for the current duration of the arrangement only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
| **&nbsp;&nbsp;&nbsp;&nbsp;Expenses After** | **Class A** | **Investor** | **Class I** | **SIMPLE** |
|  |  | **Class** |  | **Class** |
| &nbsp;&nbsp;&nbsp;&nbsp;1 Year | $&nbsp;&nbsp;&nbsp;&nbsp; 183 | $&nbsp;&nbsp;&nbsp;&nbsp; 143 | $&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;41 | $&nbsp;&nbsp;&nbsp;&nbsp; 119 |
| &nbsp;&nbsp;&nbsp;&nbsp;3 Years | $&nbsp;&nbsp;&nbsp;&nbsp; 372 | $&nbsp;&nbsp;&nbsp;&nbsp; 427 | $&nbsp;&nbsp;&nbsp;&nbsp; 172 | $&nbsp;&nbsp;&nbsp;&nbsp; 384 |
| &nbsp;&nbsp;&nbsp;&nbsp;5 Years | $&nbsp;&nbsp;&nbsp;&nbsp; 577 | $&nbsp;&nbsp;&nbsp;&nbsp; 732 | $&nbsp;&nbsp;&nbsp;&nbsp; 315 | $&nbsp;&nbsp;&nbsp;&nbsp; 670 |
| &nbsp;&nbsp;&nbsp;&nbsp;10 Years | $1168 | $1598 | $&nbsp;&nbsp;&nbsp;&nbsp; 731 | $1483 |

---

**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

<br> (NYLIM) NL249 MSSTB01 -02/23

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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 279% of the average value of its portfolio.

**Principal Investment Strategies** 

The Fund, under normal circumstances, invests at least 80% of its assets (net assets plus any borrowings for investment purposes) in debt securities.

Under normal circumstances, the Fund invests at least 80% of net assets in investment grade quality bonds of various types as rated by a nationally recognized statistical rating organization ("NRSRO") (such bonds rated BBB- or higher, or Baa3 or higher), or if unrated, judged to be of comparable quality by NYL Investors LLC, the Fund's Subadvisor. The Fund may invest up to 20% of its net assets in bonds rated below investment grade by a NRSRO (such as bonds rated lower than BBB- and Baa3), commonly referred to as "high yield" or "junk" bonds. In the event NRSROs assign different ratings to the same security, the Fund will apply the lower rating if rated differently by two NRSROs, and will apply the middle rating if rated differently by three NRSROs.

The Fund's principal investments include investment grade corporate credit and securitized assets, including structured credit, collateralized loan obligations, asset-backed securities, residential mortgage-backed securities, commercial mortgage-backed securities and collateralized mortgage obligations.

The Fund attempts to manage interest rate risk through its management of the average duration of the securities it holds in its portfolio. Under normal conditions, the Fund will maintain its average dollar-weighted duration range between one and three years. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. The longer a security's duration, the more sensitive it will be to changes in interest rates.

The Fund may also invest in futures to seek to enhance returns or reduce the risk of loss by hedging certain of its holdings.

**Investment Process:** The Subadvisor seeks to generate consistent, risk-adjusted excess returns by conducting bottom-up fundamental research as the basis for investment selection.

Core to the Subadvisor's objective is capital preservation through loss-avoidance by constructing a well-diversified portfolio with a long-term focus. Underlying investment opportunities are based on the financial condition and competitiveness of individual companies. The Subadvisor also invests in companies that the Subadvisor believes have a high margin of safety and are leaders in industries with high barriers to entry.

The Subadvisor prefers companies with positive free cash flow, solid asset coverage and management teams with strong track records. In virtually every phase of the investment process, the Subadvisor attempts to control risk and limit defaults.

The Subadvisor's investment process relies on a comprehensive fundamental investment discipline, including, but not limited to, consideration of environmental, social and governance ("ESG") factors that may be material to a company's performance and prospects. In addition to internal research, the Subadvisor may use third-party ESG data to compare internal views with external perspectives.

The Subadvisor may sell a security if it believes the security will no longer contribute to meeting the investment objective of the Fund.

**Principal Risks** 

You can lose money by investing in the Fund. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. The investments selected by the Subadvisor may underperform the market in which the Fund invests or other investments. The Fund may receive large purchase or redemption orders which may have adverse effects on performance if the Fund were required to sell securities, invest cash or hold a relatively large amount of cash at times when it would not otherwise do so.

The principal risks of investing in the Fund are summarized below.

**Net Asset Value Risk:** The Fund is not a money market fund, does not attempt to maintain a stable net asset value ("NAV"), and is not subject to the rules that govern the quality, maturity, liquidity and other features of securities that money market funds may purchase. Under normal conditions, the Fund's investments may be more susceptible than those of a money market fund to interest rate risk, valuation risk, credit risk and other risks relevant to the Fund's investments. The Fund's NAV per share will fluctuate.

**Market Risk:** Changes in markets may cause the value of investments to fluctuate, which could cause the Fund to underperform other funds with similar investment objectives and strategies. Such changes may be rapid and unpredictable. From time to time, markets may experience periods of stress as a result of various market and economic factors for potentially prolonged periods that may result in: (i) increased market volatility; (ii) reduced market liquidity; and (iii) increased redemptions of shares. Such conditions may add significantly to the risk of volatility in the net asset value of the Fund's shares.

**Portfolio Management Risk:** The investment strategies, practices and risk analyses used by the Subadvisor may not produce the desired results or expected returns. The Subadvisor may give consideration to certain ESG criteria when evaluating an investment opportunity. The application of ESG criteria may result in the Fund (i) having exposure to certain securities or industry sectors that are significantly different than the composition of the Fund's benchmark; and (ii) performing differently than other funds and strategies in its peer group that do not take into account ESG criteria or the Fund's benchmark.

**Yield Risk:** There can be no guarantee that the Fund will achieve or maintain any particular level of yield.

**Debt Securities Risk:** The risks of investing in debt or fixed-income securities include (without limitation): (i) credit risk, e.g., the issuer or guarantor of a debt security may be unable or unwilling (or be perceived as unable or unwilling) to make timely principal and/or interest payments or otherwise honor its obligations, or changes in an issuer's credit rating or the market's perception of an issuer's creditworthiness may affect the value of the Fund's investments; (ii) maturity risk, e.g., a debt security with a longer maturity may fluctuate in value more than one with a shorter maturity; (iii) market risk, e.g., low demand for debt securities may negatively impact their price; (iv) interest rate risk, e.g., when interest rates go up, the value of a debt security generally goes down, and when interest rates go down, the value of a debt security generally goes up (long-term debt securities are generally more susceptible to interest rate risk than short-term debt securities); and (v) call or prepayment risk, e.g., during a period of falling interest rates, the issuer may redeem a security by repaying it early, which may reduce the Fund's income if the proceeds are reinvested at lower interest rates.

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Interest rate risk is the risk that the value of the Fund's investments in fixed income or debt securities will change because of changes in interest rates. There is a risk that interest rates across the financial system may change, possibly significantly and/or rapidly. Changes in interest rates or a lack of market participants may lead to decreased liquidity and increased volatility in the fixed-income or debt markets, making it more difficult for the Fund to sell its fixed-income or debt holdings. Decreased liquidity in the fixed-income or debt markets also may make it more difficult to value some or all of the Fund's fixed-income or debt holdings. For most fixed-income investments, when market interest rates fall, prices of fixed-rate debt securities rise. However, when market interest rates fall, prices of certain variable and fixed-rate debt securities may be adversely affected (i.e., falling interest rates bring the possibility of prepayment risk, as an instrument may be redeemed before maturity). Very low or negative interest rates may magnify interest rate risk. Low interest rates (or negative interest rates) may magnify the risks associated with rising interest rates. The Fund may also be subject to heightened interest rate risk when the Federal Reserve raises interest rates. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from Fund performance to the extent the Fund is exposed to such interest rates and/or volatility. Other factors that may affect the value of debt securities include, but are not limited to, economic, political, public health, and other crises and responses by governments and companies to such crises.

Not all U.S. government debt securities are guaranteed by the U.S. government—some are backed only by the issuing agency, which must rely on its own resources to repay the debt. The Fund's yield will fluctuate with changes in short-term interest rates.

**High-Yield Securities Risk:** Investments in high-yield securities or non-investment grade securities (commonly referred to as "junk bonds") are considered speculative because investments in such securities present a greater risk of loss than investments in higher quality securities. Such securities may, under certain circumstances, be less liquid than higher rated securities. These securities pay investors a premium (a high interest rate or yield) because of the potential illiquidity and increased risk of loss. These securities can also be subject to greater price volatility. In times of unusual or adverse market, economic or political conditions, these securities may experience higher than normal default rates.

**Mortgage Pass-Through Securities Risk:** Investments in mortgage pass-through securities are subject to similar market risks as fixed-income securities, which include, but are not limited to, interest rate risk, credit risk, prepayment risk, and extension risk.

**Floating Rate Notes and Variable Rate Notes Risk:** Floating and variable rate notes provide for a periodic adjustment in the interest rate paid on the securities. The rate adjustment intervals may be regular and range from daily up to annually, or may be based on an event, such as a change in the prime rate. Floating and variable rate notes may be subject to greater liquidity risk than other debt securities, meaning that there may be limitations on the Fund's ability to sell the securities at any given time. Securities with floating interest rates generally are less sensitive to interest rate changes, but may decline in value if their interest rates do not rise as much or as fast as interest rates in general. Floating rate loans and other similar debt obligations that lack financial maintenance covenants or possess fewer or contingent financial maintenance covenants and other financial protections for lenders and investors (sometimes referred to as "covenant-lite" loans or obligations) are generally subject to more risk than investments that contain traditional financial maintenance covenants and financial reporting requirements. The terms of many floating rate notes and other instruments are tied to the London Interbank Offered Rate ("LIBOR") or the Secured Overnight Financing Rate ("SOFR"), which function as reference rates or benchmarks. Certain LIBOR tenors were discontinued at the end of 2021, but the most widely used LIBOR tenors may continue to be provided on a representative basis until mid-2023. There remains uncertainty regarding the future use of LIBOR and the nature of any replacement rate, such as SOFR. As such, the potential effect of a transition away from LIBOR tenors may cause increased volatility and illiquidity in the markets for instruments with terms tied to such LIBOR tenors or other adverse consequences, such as decreased yields and reduction in value, for these instruments. This may adversely affect the Fund and its investments in such instruments.

**Mortgage-Related and Other Asset-Backed Securities Risk:** Investments in mortgage-related securities (such as mortgage-backed securities) and other asset-backed securities generally involve a stream of payments based on the underlying obligations. These payments, which are often part interest and part return of principal, vary based on the rate at which the underlying borrowers repay their loans or other obligations. Asset-backed securities are subject to the risk that borrowers may default on the underlying obligations and that, during periods of falling interest rates, these obligations may be called or prepaid and, during periods of rising interest rates, obligations may be paid more slowly than expected. Impairment of the underlying obligations or collateral, such as by non-payment, will reduce the security's value. Enforcing rights against such collateral in events of default may be difficult or insufficient. The value of these securities may be significantly affected by changes in interest rates, the market's perception of issuers, and the creditworthiness of the parties involved. These securities may have a structure that makes their reaction to interest rate changes and other factors difficult to predict, making their value highly volatile.

**Derivatives Risk:** Derivatives are investments whose value depends on (or is derived from) the value of an underlying instrument, such as a security, asset, reference rate or index. Derivative strategies may be riskier than investing directly in the underlying instrument and often involve leverage, which may exaggerate a loss, potentially causing the Fund to lose more money than it originally invested and would have lost had it invested directly in the underlying instrument. Derivatives may be difficult to sell, unwind and/or value. Derivatives may also be subject to counterparty risk, which is the risk that the counterparty (the party on the other side of the transaction) on a derivative transaction will be unable or unwilling to honor its contractual obligations to the Fund. Futures may be more volatile than direct investments in the instrument underlying the contract, and may not correlate perfectly to the underlying instrument. Futures and other derivatives also may involve a small initial investment relative to the risk assumed, which could result in losses greater than if they had not been used. Due to fluctuations in the price of the underlying instrument, the Fund may not be able to profitably exercise an option and may lose its entire investment in an option. To the extent that the Fund writes or sells an option, if the decline in the value of the underlying instrument is significantly below the exercise price in the case of a written put option or increase above the exercise price in the case of a written call option, the Fund could experience a substantial loss. Derivatives may also increase the expenses of the Fund.

**Liquidity and Valuation Risk:** The Fund's investments may be illiquid at the time of purchase or liquid at the time of purchase and subsequently become illiquid due to, among other things, events relating to the issuer of the securities, market events, operational issues, economic conditions, investor perceptions or lack of market participants. The lack of an active trading market may make it difficult to sell or obtain an accurate price for a security. If market conditions or issuer specific developments make it difficult to value securities, the Fund may value these securities using more subjective methods, such as fair value pricing. In such cases, the value determined for a security could be different than the value realized upon such security's sale. As a result, an investor could pay more than the market value when buying shares or receive less than the market value when selling shares. This could affect the

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proceeds of any redemption or the number of shares an investor receives upon purchase. The Fund is subject to the risk that it could not meet redemption requests within the allowable time period without significant dilution of remaining investors' interests in the Fund. To meet redemption requests or to raise cash to pursue other investment opportunities, the Fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the Fund's performance. These risks are heightened for fixed-income instruments when interest rates are low or rapidly increasing.

**Money Market/Short-Term Securities Risk:** To the extent the Fund holds cash or invests in money market or short-term securities, the Fund may be less likely to achieve its investment objective. In addition, it is possible that the Fund's investments in these instruments could lose money.

**Past Performance**

The following bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns compare with those of a broad-based securities market index over time. Sales loads, if any, are not reflected in the bar chart. If they were, returns would be less than those shown. The Fund has selected the Bloomberg 1-3 Year U.S. Government/Credit Bond Index as its primary benchmark.

Index returns reflect no deductions for fees, expenses or taxes, except for foreign withholding taxes where applicable.

Performance data for the classes varies based on differences in their fee and expense structures. Performance data is not shown for classes with less than one calendar year of performance. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Please visit newyorklifeinvestments.com/funds for more recent performance information.

Effective December 5, 2019, the Fund's investment objective and principal investment strategies changed. Prior to that date, the Fund operated as an index fund and sought to match the return of its former benchmark gross of fees. The past performance in the bar chart and table prior to that date reflects the Fund's prior investment objective and principal investment strategies.

#### Annual Returns, Class I Shares

#### (by calendar year 2013-2022)
![PerformanceBarChartData(2013:-2.43, 2014:5.75, 2015:0.16, 2016:2.16, 2017:3.19, 2018:-0.57, 2019:8.49, 2020:3.25, 2021:-0.3, 2022:-4.18)](img_9fa1cd4bcd374f1.jpg)

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| | |
|:---|:---|
| **Best Quarter** | **Best Quarter** |
| 2020, Q2 | 5.58% |
| **Worst Quarter** | **Worst Quarter** |
| 2020, Q1 | -4.05% |

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

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| | | | | |
|:---|:---|:---|:---|:---|
| | <br>Inception<br>| <br>&nbsp;&nbsp;&nbsp;&nbsp; 1 Year<br> | <br>5 Years<br> | 10 Years or<br>Since<br>Inception |
| Return Before Taxes |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Class I | 1/2/1991 | -4.18% | 1.25% | 1.49% |
| Return After Taxes on Distributions |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Class I |  | -5.04% | -0.30% | 0.10% |
| Return After Taxes on Distributions and Sale of Fund Shares |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Class I |  | -2.47% | 0.44% | 0.62% |
| Return Before Taxes |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Class A | 1/2/2004 | -5.48% | 0.33% | 0.87% |
| &nbsp;&nbsp;&nbsp;Investor Class | 2/28/2008 | -5.21% | 0.10% | 0.66% |
| &nbsp;&nbsp;&nbsp;SIMPLE Class | 8/31/2020 | -4.95% | N/A | -2.36% |
| Bloomberg 1-3 Year U.S. Government/Credit Bond Index<sup>1</sup> | Bloomberg 1-3 Year U.S. Government/Credit Bond Index<sup>1</sup> | -3.69% | 0.92% | 0.88% |

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1. The Bloomberg 1-3 Year U.S. Government/Credit Bond Index is an unmanaged index comprised of investment grade, U.S. dollar-denominated, fixed-rate Treasuries, government-related and corporate securities, with maturities of one to three years.

After-tax returns are calculated using the highest individual federal marginal income tax rates in effect at the time of each distribution or capital gain or upon the sale of Fund shares, and do not reflect the impact of state and local taxes. In some cases, the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of shares at the end of the measurement period. Actual after-tax returns depend on your tax situation and may differ from those shown. After-tax returns are not relevant if you hold your shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns shown are for Class I shares. After-tax returns for the other share classes may vary.

**Management**

New York Life Investment Management LLC serves as the Manager. NYL Investors LLC serves as the Subadvisor. The individuals listed below are jointly and primarily responsible for day-to-day portfolio management.

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| | | |
|:---|:---|:---|
| **Subadvisor** | **Portfolio Managers** | **Service Date** |

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| | | |
|:---|:---|:---|
| NYL Investors LLC  | Kenneth Sommer, Managing Director | Since 2017 |
|  | Matthew Downs, Senior Director | Since February 2023 |
|  | AJ Rzad, Senior Managing Director | Since 2018 |

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**How to Purchase and Sell Shares**

You may purchase or sell shares of the Fund on any day the Fund is open for business by contacting your financial adviser or financial intermediary firm, or by contacting the Fund by telephone at **800-624-6782**, by mail at MainStay Funds, P.O. Box 219003, Kansas City, MO 64121-9000, by overnight mail to 430 West 7<sup>th</sup> Street, Suite 219003, Kansas City, MO 64105-1407, or by accessing our website at newyorklifeinvestments.com/accounts. SIMPLE Class shares are generally only available to SIMPLE IRA Plan accounts. SIMPLE Class shares are generally not available to retail accounts. Generally, an initial investment minimum of $1,000 applies if you invest in Investor Class or SIMPLE Class shares, $15,000 for Class A shares and $1,000,000 for individual investors in Class I shares investing directly (i) with the Fund or (ii) through certain private banks and trust companies that have an agreement with NYLIFE Distributors LLC, the Fund's principal underwriter and distributor, or its affiliates. A subsequent investment minimum of $50 applies to investments in Investor Class shares. However, for Investor Class shares purchased through AutoInvest, MainStay's systematic investment plan, a $500 initial investment minimum and a $50 minimum for subsequent purchases applies. Class A and SIMPLE Class shares have no subsequent investment minimum. Institutional shareholders in Class I shares have no initial or subsequent investment minimums.

Certain financial intermediaries through whom you may invest may impose their own investment minimums, fees, policies and procedures for purchasing and selling Fund shares, which are not described in this Prospectus or the Statement of Additional Information, and which will depend on the policies, procedures and trading platforms of the financial intermediary. Consult a representative of your financial intermediary about the availability of shares of the Fund and the intermediary's policies, procedures and other information.

**Tax Information**

The Fund's distributions are generally taxable to you as ordinary income, capital gains, or a combination of the two, unless you are investing through a tax-deferred arrangement, such as a 401(k) plan or an individual retirement account.

**Compensation to Financial Intermediary Firms**

If you purchase Fund shares through a financial intermediary firm (such as a broker/dealer or bank), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the financial intermediary firm or your financial adviser to recommend the Fund over another investment. Ask your financial adviser or visit your financial intermediary firm's website for more information.

"New York Life Investments" is both a service mark, and the common trade name, of certain investment advisors affiliated with New York Life Insurance Company.

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