Total

MainStay Balanced Fund

MainStay Balanced Fund

Investment Objective

The Fund seeks total return.

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 130 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 Balanced 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)	3.00%		3.00%		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 Balanced 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]	0.70%	0.70%	0.70%		0.70%	0.70%	0.70%	0.70%	0.70%	0.70%
Distribution and/or Service (12b-1) Fees		0.25%	0.25%	1.00%		1.00%	none	none	0.25%	0.50%	none
Other Expenses		0.17%	0.40%	0.40%		0.40%	0.17%	0.27%	0.27%	0.27%	0.07%
Acquired (Underlying) Fund Fees and Expenses		0.01%	0.01%	0.01%		0.01%	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses		1.13%	1.36%	2.11%		2.11%	0.88%	0.98%	1.23%	1.48%	0.78%

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 Balanced Fund - USD ($)	Class A	Investor Class	Class B	Class C	Class I	Class R1	Class R2	Class R3	Class R6
1 Year	$ 412	$ 434	$ 714	$ 314	$ 90	$ 100	$ 125	$ 151	$ 80
3 Years	648	718	961	661	281	312	390	468	249
5 Years	904	1,022	1,334	1,134	488	542	676	808	433
10 Years	$ 1,633	$ 1,886	$ 2,250	$ 2,441	$ 1,084	$ 1,201	$ 1,489	$ 1,768	$ 966

Assuming no redemption

Expense Example No Redemption - MainStay Balanced Fund - USD ($)	Class B	Class C
1 Year	$ 214	$ 214
3 Years	661	661
5 Years	1,134	1,134
10 Years	$ 2,250	$ 2,441

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 194% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests approximately 60% of its assets (net assets plus any borrowings for investment purposes) in stocks and 40% of its assets in fixed-income securities (such as bonds) and cash equivalents. Although this 60/40 ratio may vary, under normal market conditions, the Fund will invest at least 25% of its assets in fixed-income securities. Asset allocation decisions are made by New York Life Investment Management LLC, the Fund’s Manager, based on its tactical view of the market. The Fund may invest in exchange-traded funds (“ETFs”), including ETFs advised by affiliates of the Manager and ETFs advised by unaffiliated advisers, to facilitate rebalancing the Fund’s allocation between equity and fixed-income exposures.

The Fund may invest up to 20% of its net assets in foreign securities, but only in countries that NYL Investors LLC (“NYL Investors”), the Subadvisor for the fixed-income portion of the Fund, and MacKay Shields LLC (“MacKay Shields”), the Subadvisor for the equity portion of the Fund, consider stable, and only in securities considered to be of high quality. The Fund may also invest in derivatives, such as futures and options, to try to enhance returns or reduce the risk of loss by hedging certain of its holdings.

Under normal market conditions, the Subadvisors will seek to keep the portfolio fully invested rather than taking temporary cash positions with respect to their portions of the Fund's assets. The Subadvisors will sell a security if it becomes relatively overvalued, if better opportunities are identified, or if they determine that the initial investment expectations are not being met.

Equity Investment Process: MacKay Shields generally invests in mid-capitalization, value oriented stocks, but may also invest in large-capitalization, value-oriented stocks. MacKay Shields considers mid-capitalization stocks to be those stocks issued by companies with a market capitalization that, at the time of investment, are similar to the companies in the Russell Midcap^® Index (which ranged from $824 million to $78.721 billion as of December 31, 2019), the S&P MidCap 400^® Index (which ranged from $1.104 billion to $12.638 billion as of December 31, 2019), or a universe selected from the smallest 800 companies of the largest 1,000 companies, ranked by market capitalization. Mid-capitalization stocks are common stocks of mid-size U.S. companies that tend to be well known and tend to have a large amount of stock outstanding compared to small-capitalization stocks.

"Value" stocks are stocks that MacKay Shields determines (1) have strong or improving fundamental characteristics and (2) have been overlooked by the marketplace so that they are undervalued or "underpriced" relative to the rest of the Fund's universe.

The Fund seeks to construct a broadly diversified portfolio across countries, sectors and industries using quantitative analysis to identify undervalued and overvalued securities. MacKay Shields uses a quantitative model that is designed to evaluate individual issuers and securities across valuation, momentum and market sentiment criteria. MacKay Shields also conducts a qualitative review of the results of the quantitative analysis. In certain cases, MacKay Shields may deviate from positions or weightings suggested by the quantitative analysis to account for events and conditions that may not be quantifiable by the analysis, such as company-specific and market events. MacKay Shields regularly evaluates the quantitative model and, from time to time, may adjust the metrics and data underlying its quantitative analysis for a variety of reasons, including, without limitation, to account for changing market, financial or economic conditions. Investments are recommended using an objective, disciplined and broadly-applied process, while seeking to limit exposure to risk.

Fixed-Income Investment Process: NYL Investors generally invests in U.S. government securities, mortgage-backed securities, asset-backed securities and investment grade corporate bonds. It selects fixed-income securities based on their credit quality, duration and price. The fixed-income portion of the portfolio normally has an intermediate term duration that ranges from three to five years.

The Fund's investments may include variable rate notes, floating rate notes and mortgage-related securities (including mortgage-backed) securities, which are debt securities whose values are based on underlying pools of mortgages, and asset-backed securities, which are debt securities whose values are based on underlying pools of credit receivables.

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 Subadvisors 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.

Multi-Manager Risk: The Fund’s performance relies on the selection and monitoring of the Subadvisors as well as how the Fund’s assets are allocated among those Subadvisors. Performance will also depend on the Subadvisors’ skill in implementing their respective strategy or strategies. The Subadvisors’ investment strategies may not always be complementary to one another and, as a result, the Subadvisors may make decisions that conflict with one another, which may adversely affect the Fund’s performance. For example, a Subadvisor may purchase an investment for the Fund at the same time that another Subadvisor sells the investment, resulting in higher expenses without accomplishing any net investment result. Alternatively, multiple Subadvisors could purchase the same investment at the same time, causing the Fund to pay higher expenses because they did not aggregate their transactions. The multi-manager approach may also cause the Fund to invest a substantial percentage of its assets in certain types of securities, which could expose the Fund to greater risks as associated with those types of securities and lead to large beneficial or detrimental effects on the Fund’s performance. The Manager may influence a Subadvisor in terms of its management of a portion of the Fund’s assets, including hedging practices, investment exposure and risk management.

A Subadvisor may underperform the market generally and may underperform other subadvisors that the Manager could have selected. One or more Subadvisors may have limited or no experience in managing assets of a registered investment company, which is subject to daily inflows and outflows of investor cash and certain legal and tax-related restrictions on its investments and operations.

Portfolio Management Risk: The investment strategies, practices and risk analyses used by a Subadvisor may not produce the desired results. In addition, the Fund may not achieve its investment objective, including during periods in which a Subadvisor takes temporary positions in response to unusual or adverse market, economic or political conditions, or other unusual or abnormal circumstances.

Investments selected using quantitative methods or based on models that analyze information and data (“quantitative tools”) may perform differently from the market as a whole. The quantitative tool used by the Subadvisor, and the investments selected based on the quantitative tool, may not perform as expected. The quantitative tool may contain certain assumptions in construction and implementation that may adversely affect the Fund’s performance. There may also be technical issues with the construction and implementation of quantitative tools (for example, software or other technology malfunctions, or programming inaccuracies). In addition, the Fund’s performance will reflect, in part, the Subadvisor’s ability to make active qualitative decisions and timely adjust the quantitative tool, including the tool’s underlying metrics and data.

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

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.

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.

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.

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).

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.

Exchange-Traded Fund Risk: The risks of owning an ETF generally reflect the risks of owning the securities in which the ETF invests or is designed to track, although lack of liquidity in an ETF could result in it being more volatile than its underlying portfolio securities. Disruptions in the markets for the securities underlying ETFs purchased or sold by the Fund could result in losses on the Fund's investment in ETFs. ETFs also have management fees and transaction costs that may make them more expensive than owning the underlying securities directly.

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 expose the Fund to greater risk than if it had invested 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 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 asset, the Fund may not be able to profitably exercise an option and may lose its entire investment in an option. Derivatives may also increase the expenses of the Fund.

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. The terms of many floating rate notes and other instruments are tied to the London Interbank Offered Rate (“LIBOR”), which functions as a reference rate or benchmark. It is anticipated that LIBOR will be discontinued at the end of 2021, which may cause increased volatility and illiquidity in the markets for instruments with terms tied to LIBOR or other adverse consequences for these instruments. These events 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. The ability of the Fund to successfully utilize these instruments may depend on the ability of the Subadvisor to forecast interest rates and other economic factors correctly. 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.

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.

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 Fund shares or receive less than the market value when selling Fund shares. This could affect the 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.

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 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 two broad-based securities market indices, as well as a composite index. The Fund has selected the Russell Midcap^® Value Indexas its primary benchmark. The Russell Midcap^® Value Index measures the performance of the mid-cap value segment of the U.S. equity universe. It includes those Russell Midcap^® Index companies with lower price-to-book ratios and lower forecasted growth values. The Fund has selected the Bloomberg Barclays U.S. Intermediate Government/Credit Bond Index as its secondary benchmark. The Bloomberg Barclays U.S. Intermediate Government/Credit Bond Index measures the performance of U.S. dollar-denominated U.S. treasuries, government-related and investment grade U.S. corporate securities that have a remaining maturity of greater than one year and less than ten years. The Fund has selected the Balanced Composite Index as an additional benchmark. The Balanced Composite Index consists of the Russell Midcap^® Value Index and the Bloomberg Barclays U.S. Intermediate Government/Credit Bond Index weighted 60%/40%, respectively.

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.

The Fund’s equity subadvisor changed effective January 1, 2018 due to an organizational restructuring whereby all investment personnel of Cornerstone Capital Management Holdings LLC, the former equity subadvisor, transitioned to MacKay Shields LLC.

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

Best Quarter
1Q/13	9.28	%
Worst Quarter
4Q/18	-9.87	%

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

Average Annual Returns - MainStay Balanced Fund	1 Year	5 Years or Since Inception	10 Years	Inception Date
Class I	16.68%	4.90%	8.41%	May 01, 1989
Class A	9.95%	3.47%	7.53%	Jan. 02, 2004
Investor Class	9.72%	3.29%	7.34%	Feb. 28, 2008
Class B	10.26%	3.35%	7.14%	Jan. 02, 2004
Class C	14.27%	3.69%	7.15%	Dec. 30, 2002
Class R1	16.58%	4.81%	8.31%	Jan. 02, 2004
Class R2	16.28%	4.58%	8.05%	Jan. 02, 2004
Class R3	15.97%	4.27%	7.76%	Apr. 28, 2006
Class R6	16.82%	4.25%		Feb. 28, 2017
After Taxes on Distributions | Class I	15.52%	3.28%	6.93%
After Taxes on Distributions and Sale of Fund Shares | Class I	10.53%	3.47%	6.47%
Russell Midcap® Value Index (reflects no deductions for fees, expenses, or taxes)	27.06%	7.62%	12.41%
Bloomberg Barclays U.S. Intermediate Government/Credit Bond Index (reflects no deductions for fees, expenses, or taxes)	6.80%	2.57%	3.05%
Balanced Composite Index (reflects no deductions for fees, expenses, or taxes)	18.90%	5.79%	8.84%

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 $250,000 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 $1 billion; 0.65% on assets from $1 billion to $2 billion; and 0.60% 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.