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MainStay Epoch U.S. Equity Yield Fund

MainStay Epoch U.S. Equity Yield Fund

Investment Objective

The Fund seeks current income and capital appreciation.

Fees and Expenses of the Fund

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may be required to pay a commission or other transaction charge to your financial intermediary for effecting transactions in a class of shares of the Fund that has no initial sales charge, contingent deferred sales charge, or other asset-based fee for sales or distribution, such as Class I or Class R6 shares. These commissions are not reflected in the fee and expense table or expense example below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the MainStay Funds. This amount may vary depending on the MainStay Fund in which you invest. 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 101 of the Prospectus and Appendix A – Intermediary-Specific Sales Charge Waivers and Discounts, and in the "Alternative Sales Arrangements" section on page 123 of the Statement of Additional Information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees - MainStay Epoch U.S. Equity Yield Fund	Class A		Investor Class		Class B	[1]	Class C	Class I	Class R1	Class R2	Class R3	Class R6
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.50%		5.50%		none		none	none	none	none	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lesser of the original offering price or redemption proceeds)	none	[2]	none	[2]	5.00%		1.00%	none	none	none	none	none

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

Annual Fund Operating Expenses - MainStay Epoch U.S. Equity Yield Fund		Class A	Investor Class	Class B	[2]	Class C	Class I	Class R1	Class R2	Class R3	Class R6
Management Fees (as an annual percentage of the Fund's average daily net assets)	[1]	0.69%	0.69%	0.69%		0.69%	0.69%	0.69%	0.69%	0.69%	0.69%
Distribution and/or Service (12b-1) Fees		0.25%	0.25%	1.00%		1.00%	none	none	0.25%	0.50%	none
Other Expenses		0.14%	0.41%	0.41%		0.41%	0.14%	0.24%	0.24%	0.24%	0.05%
Total Annual Fund Operating Expenses		1.08%	1.35%	2.10%		2.10%	0.83%	0.93%	1.18%	1.43%	0.74%
Waivers / Reimbursements	[3]	none	(0.01%)	(0.01%)		(0.01%)	(0.10%)	none	none	none	(0.01%)
Total Annual Fund Operating Expenses After Waivers / Reimbursements	[3]	1.08%	1.34%	2.09%		2.09%	0.73%	0.93%	1.18%	1.43%	0.73%

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 (except as indicated with respect to Class B and Class C shares). The Example reflects Class B shares converting into Investor Class shares in years 9-10; fees could be lower if you are eligible to convert to Class A shares instead. 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:

Assuming redemption at end of period

Expense Example - MainStay Epoch U.S. Equity Yield Fund - USD ($)	Class A	Investor Class	Class B	Class C	Class I	Class R1	Class R2	Class R3	Class R6
1 Year	$ 654	$ 679	$ 712	$ 312	$ 75	$ 95	$ 120	$ 146	$ 75
3 Years	875	953	957	657	255	296	375	452	236
5 Years	1,113	1,248	1,328	1,128	451	515	649	782	410
10 Years	$ 1,795	$ 2,084	$ 2,239	$ 2,430	$ 1,016	$ 1,143	$ 1,432	$ 1,713	$ 917

Assuming no redemption

Expense Example No Redemption - MainStay Epoch U.S. Equity Yield Fund - USD ($)	Class B	Class C
1 Year	$ 212	$ 212
3 Years	657	657
5 Years	1,128	1,128
10 Years	$ 2,239	$ 2,430

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 18% of the average value of its portfolio.

Principal Investment Strategies

The Fund generally invests in a diversified portfolio consisting of equity securities of U.S. companies that have a history of attractive dividend yields and positive growth in operating cash flow. Under normal circumstances, the Fund invests at least 80% of its assets (net assets plus any borrowings for investment purposes) in equity securities of dividend-paying U.S. companies across all market capitalizations. Generally, U.S. companies are companies organized in the U.S. that trade primarily in U.S. securities markets. The Fund may invest up to 15% of its net assets in foreign securities. Generally, foreign securities are issued by companies organized outside the U.S. or that trade primarily in non-U.S. securities markets.

Investment Process: Epoch Investment Partners, Inc., the Fund's Subadvisor, invests primarily in companies that generate increasing levels of free cash flow and have management teams that the Subadvisor believes allocate free cash flow effectively to create shareholder value.

The security selection process focuses on free-cash-flow analytics as opposed to traditional accounting-based metrics. The Subadvisor seeks to identify companies with a consistent, straightforward ability to both generate free cash flow and to intelligently allocate it among internal reinvestment opportunities, acquisitions, dividends, share repurchases and/or debt reduction.

The Subadvisor seeks to find and invest in companies that meet its definition of quality-companies that are free cash flow positive or becoming free cash flow positive, that are debt free or deleveraging, and that are led by strong management. The Subadvisor evaluates whether a company has a focus on shareholder yield by analyzing the company's existing cash dividend, the company's share repurchase activities, and the company's debt reduction activities as well as the likelihood of positive changes to each of these criteria, among other factors.

The Subadvisor may sell or reduce a position in a security when it believes its investment objectives have been met or if the investment thesis is failing to materialize. The Subadvisor may also sell or reduce a position in a security if it sees an interruption to the dividend policy, a deterioration in fundamentals or when the security is deemed less attractive relative to another security on a return/risk basis.

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.

Market Risk: The value of the Fund’s investments may fluctuate because of changes in the markets in which the Fund invests, 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 for potentially prolonged periods that may result in: (i) increased market volatility; (ii) reduced market liquidity; and (iii) increased redemptions of Fund 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. In addition, the Fund may not achieve its investment objective, including during periods in which the Subadvisor takes temporary positions in response to unusual or adverse market, economic or political conditions, or other unusual or abnormal circumstances.

Equity Securities Risk: Investments in common stocks and other equity securities are particularly subject to the risk of changing economic, stock market, industry and company conditions and the risks inherent in the portfolio managers' ability to anticipate such changes that can adversely affect the value of the Fund's holdings.

Dividend-Paying Stock Risk:The Fund’s emphasis on equity and equity-related securities that produce income or other distributions subjects the Fund to the risk that such securities may fall out of favor with investors and underperform the market. Depending upon market conditions, income producing stocks that meet the Fund’s investment criteria may not be widely available and/or may be highly concentrated in only a few market sectors. This may limit the ability of the Fund to produce current income while remaining fully diversified. Also, an issuer may reduce or eliminate its income payments or other distributions, particularly during a market downturn. The distributions received by the Fund may not qualify as income for Fund investors.

Value Stock Risk: Value stocks may never reach what the Subadvisor believes is their full value or they may go down in value. In addition, different types of stocks tend to shift in and out of favor depending on market and economic conditions, and therefore the Fund's performance may be lower or higher than that of funds that invest in other types of equity securities.

Market Capitalization Risk: To the extent the Fund invests in securities issued by small-, mid-, or large-cap companies, the Fund will be subject to the risks associated with securities issued by companies of the applicable market capitalization.  Securities of small-cap and mid-cap companies may be subject to greater price volatility, significantly lower trading volumes, cyclical, static or moderate growth prospects and greater spreads between their bid and ask prices than securities of larger companies. Smaller capitalization companies frequently rely on narrower product lines and niche markets and may be more vulnerable to adverse business or market developments.  Securities issued by larger companies may have less growth potential and may not be able to attain the high growth rates of successful smaller companies, especially during strong economic periods.  In addition, larger companies may be less capable of responding quickly to competitive challenges and industry changes, including those resulting from improvements in technology, and may suffer sharper price declines as a result of earnings disappointments.  There is a risk that the securities issued by companies of a certain market capitalization may underperform the broader market at any given time.

Foreign Securities Risk: Investments in foreign (non-U.S.) securities may be riskier than investments in U.S. securities. Foreign regulatory regimes and securities markets can have less stringent investor protections and disclosure standards and less liquid trading markets than U.S. regulatory regimes and securities markets, and can experience political, social and economic developments that may affect the value of the Fund's investments in foreign securities. Foreign securities may also subject the Fund's investments to changes in currency rates. Changes in the value of foreign currencies may make the return on an investment increase or decrease, unrelated to the quality or performance of the investment itself. These risks may be greater with respect to securities of companies that conduct their business activities in emerging markets or whose securities are traded principally in emerging markets.

Past Performance

The following bar chart and table indicate some of the risks of investing in the Fund. The bar chart shows you how the Fund's calendar year performance has varied over time. Sales loads, if any, are not reflected in the bar chart. If they were, returns would be less than those shown. The average annual total returns table shows how the Fund's average annual total returns (before and after taxes) compare to those of a broad-based securities market index, as well as a composite index. The Fund has selected the Russell 1000^® Value Indexas its primary benchmark. The Russell 1000^® Value Index measures the performance of the large-cap value segment of the U.S. equity universe. It includes those Russell 1000^® Index companies with lower price-to-book ratios and lower expected growth values. The Fund has selected the U.S. Equity Yield Composite Index as its secondary benchmark. The U.S. Equity Yield Composite Index consists of the MSCI USA High Dividend Yield Index and the MSCI USA Minimum Volatility (USD) Index weighted at 60% and 40%, respectively. The MSCI USA High Dividend Yield Index is based on the MSCI USA Index and includes large- and mid-cap stocks. The MSCI USA High Dividend Yield Index is designed to reflect the performance of equities in the MSCI USA Index (excluding real estate investment trusts) with higher dividend income and quality characteristics than average dividend yields that are both sustainable and persistent. The MSCI USA Minimum Volatility (USD) Index aims to reflect the performance characteristics of a minimum variance strategy applied to the large- and mid-cap USA equity universe. The MSCI USA Minimum Volatility (USD) Index is calculated by optimizing the MSCI USA Index in USD for the lowest absolute risk (within a given set of constraints).

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 nylinvestments.com/funds for more recent performance information.

On September 17, 2012, the Fund changed its investment objective and principal investment strategies. Performance figures for dates prior to September 17, 2012 reflect the Fund's prior investment objective and principal investment strategies.

Annual Returns, Class I Shares (by calendar year 2010-2019)

Best Quarter
1Q/13	12.82	%
Worst Quarter
3Q/11	-16.22	%

Average Annual Total Returns (for the periods ended December 31, 2019)

Average Annual Returns - MainStay Epoch U.S. Equity Yield Fund	1 Year	5 Years or Since Inception	10 Years	Inception Date
Class I	23.97%	8.92%	11.26%	Dec. 03, 2008
Class A	16.89%	7.44%	10.37%	Feb. 03, 2009
Investor Class	16.68%	7.25%	10.22%	Nov. 16, 2009
Class B	17.52%	7.98%		Feb. 28, 2017
Class C	21.45%	7.65%	10.02%	Nov. 16, 2009
Class R1	23.85%	10.15%		Feb. 28, 2017
Class R2	23.59%	9.85%		Feb. 28, 2017
Class R3	23.27%	9.60%		Feb. 28, 2017
Class R6	24.16%	10.39%		Feb. 28, 2017
After Taxes on Distributions | Class I	22.77%	7.64%	9.66%
After Taxes on Distributions and Sale of Fund Shares | Class I	14.98%	6.78%	8.96%
Russell 1000® Value Index (reflects no deductions for fees, expenses, or taxes)	26.54%	8.29%	11.80%
U.S. Equity Yield Composite Index (reflects no deductions for fees, expenses, or taxes)	23.63%	10.63%	12.99%

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.

[1] Class B shares are closed to all new purchases as well as additional investments by existing Class B shareholders.

[2] No initial sales charge applies on investments of $1 million or more (and certain other qualified purchases). However, a contingent deferred sales charge of 1.00% may be imposed on certain redemptions made within 18 months of the date of purchase on shares that were purchased without an initial sales charge.

[1] The management fee is as follows: 0.70% on assets up to $500 million; 0.68% on assets from $500 million to $1 billion; 0.66% on assets from $1 billion to $2 billion; and 0.65% on assets over $2 billion.

[2] Class B shares are closed to all new purchases as well as additional investments by existing Class B shareholders.

[3] New York Life Investment Management LLC ("New York Life Investments") has contractually agreed to limit the transfer agency expenses charged to each of the Fund's share classes to a maximum of 0.35% of that share class's average daily net assets on an annual basis (excluding small account fees) after deducting any other applicable expense cap reimbursements or transfer agency waivers. 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) for Class I shares do not exceed 0.73%. In addition, New York Life Investments will 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) of Class R6 do not exceed those of Class I. These agreements will remain in effect until February 28, 2021, 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.