AMG Managers DoubleLine Core Plus Bond Fund

<b>AMG Managers DoubleLine Core Plus Bond Fund</b>

<b>INVESTMENT OBJECTIVE</b>

The Fund seeks to maximize total return.

<b>FEES AND EXPENSES OF THE FUND</b>

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund. If you transact in Class I shares of the Fund through a financial intermediary, you may be required to pay a commission to the financial intermediary for effecting such transactions. Such commissions are charged by the financial intermediary and are not reflected in the table or Expense Example below.

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

Annual Fund Operating Expenses - AMG Managers DoubleLine Core Plus Bond Fund		Class N	Class I	Class Z
Management Fee		0.45%	0.45%	0.45%
Distribution and Service (12b-1) Fees		0.25%	none	none
Other Expenses		0.31%	0.31%	0.23%
Acquired Fund Fees and Expenses		0.03%	0.03%	0.03%
Total Annual Fund Operating Expenses	[1]	1.04%	0.79%	0.71%
Fee Waiver and Expense Reimbursements	[2]	(0.07%)	(0.07%)	(0.07%)
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	[1],[2]	0.97%	0.72%	0.64%

<b>EXPENSE EXAMPLE</b>

This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund’s operating expenses remain the same. The Example includes the Fund’s contractual expense limitation through March 1, 2020. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:

Expense Example - AMG Managers DoubleLine Core Plus Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class N	99	324	567	1,265
Class I	74	245	432	971
Class Z	65	220	388	876

<b>PORTFOLIO TURNOVER</b>

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 69% of the average value of its portfolio.

<b>PRINCIPAL INVESTMENT STRATEGIES</b>

Under normal circumstances, the Fund invests at least 80% of its assets in fixed income securities. Fixed income securities include, but are not limited to, securities issued or guaranteed by the U.S. government or its agencies, instrumentalities or sponsored corporations; agency mortgage-backed securities; non-agency mortgage-backed securities; commercial mortgage-backed securities; asset-backed securities; foreign and domestic corporate bonds; fixed income securities issued by corporations, governments, government agencies, authorities or instrumentalities and supra-national organizations in foreign countries including emerging markets; Rule 144A securities (securities that may be sold pursuant to Rule 144A under the Securities Act of 1933); securities issued by municipalities; and other securities bearing fixed or variable interest rates of any maturity. To gain exposure to fixed income securities, the Fund may invest in other investment companies (including exchange-traded funds (“ETFs”), open-end funds and closed-end funds) advised or subadvised by DoubleLine ^® Capital LP (“DoubleLine” or the “Subadviser”), the Fund’s Subadviser.

The Fund may invest in fixed income securities of any credit quality and may invest without limit in below investment grade securities (commonly known as “junk bonds”). The Subadviser generally intends to allocate below investment grade securities broadly across industries and issuers in an attempt to reduce the impact of negative events on an industry or issuer, although it may take more focused positions from time to time. Below investment grade securities are instruments that are rated BB+ or lower by S&P Global Ratings (“S&P”), rated Ba1 or lower by Moody’s Investors Service, Inc. (“Moody’s”), or the equivalent by any other nationally recognized statistical rating organization (“NRSRO”), or if unrated, of comparable quality in the opinion of the Subadviser. The Fund may invest up to 10% of its net assets in defaulted corporate securities. The Fund might do so, for example, where the Subadviser believes the restructured enterprise valuations or liquidation valuations may exceed current market values.

The Fund may also invest in inverse floaters, interest-only and principal-only securities and senior bank loans and assignments. To gain exposure to senior bank loans and assignments, the Fund may invest in other investment companies (including ETFs, open-end funds and closed-end funds) advised or subadvised by DoubleLine.

The Fund expects to have exposure to foreign currencies, either directly through its investments in bonds denominated in local currencies or through its investments in other investment companies advised or subadvised by DoubleLine. Such investment companies may gain exposure either through the local currencies of foreign issuers or by investing in currencies directly or currency-related instruments, such as forward contracts.

The Subadviser actively manages the portfolio’s asset class exposure using a top-down approach based on analysis of sector fundamentals. Primary sectors include government/municipals, high yield, global developed credit, international sovereign debt, emerging markets, and mortgage- and asset-backed. The Subadviser generally intends to rotate portfolio assets among sectors in various markets to attempt to maximize return. Individual securities within asset classes are selected using a bottom up approach.

The Subadviser seeks to control risk by generally taking into account the following considerations:

• Security selection within a given asset class

• Relative performance of the various market sectors and asset classes

• The shape of the yield curve

• Fluctuations in the overall level of interest rates

The Subadviser also monitors the duration of the securities held by the Fund to seek to mitigate exposure to interest rate risk. Under normal circumstances, the Subadviser seeks to maintain an investment portfolio with a weighted average effective duration of no less than two years and no more than eight years. The duration of the Fund’s portfolio may vary materially from its target, from time to time, and there is no assurance that the duration of the Fund’s portfolio will meet its target.

Portfolio securities may be sold at any time. Sales may occur, for example, when the Subadviser perceives deterioration in the credit fundamentals of the issuer, believes there are negative macro political considerations that may affect the issuer, determines to take advantage of a better investment opportunity, or the individual security has reached the Subadviser’s sell target.

The Subadviser’s investment process may result in high portfolio turnover.

<b>PRINCIPAL RISKS</b>

There is the risk that you may lose money on your investment. All investments carry a certain amount of risk, and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. Below are some of the risks of investing in the Fund (either directly or through the Fund’s investments in one or more other funds). The risks are described in alphabetical order and not in the order of importance or potential exposure.

Affiliated Fund Risk— the Subadviser is subject to a potential conflict of interest in determining whether to invest the Fund’s assets in an underlying fund managed by the Subadviser, and the Subadviser may have an economic or other incentive to make or retain an investment in an affiliated fund in lieu of other investments that may also be appropriate for the Fund.

Asset-Backed and Mortgage-Backed Securities Risk—investments in asset-backed and mortgage-backed securities involve risk of severe credit downgrades, loss due to prepayments that occur earlier or later than expected, illiquidity and default.

Call Risk— call risk is the possibility that an issuer may redeem a fixed income security before maturity (a call). The increased likelihood of a call may reduce the security’s price and may result in the Fund reinvesting at lower interest rates in securities with greater credit risk.

Credit Risk—the issuer of bonds or other debt securities may be unable or unwilling, or may be perceived as unable or unwilling, to make timely interest or principal payments or otherwise honor its obligations.

Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars and exposure to non-U.S. currencies may subject the Fund to the risk that those currencies will decline in value relative to the U.S. dollar.

Defaulted and Distressed Securities Risk—investments in defaulted or distressed corporate securities involve the risk of the uncertainty of repayment on defaulted securities (e.g., a security on which a principal or interest payment is not made when due) or on obligations of distressed issuers (some of whom may be insolvent or in bankruptcy or insolvency proceedings).

Derivatives Risk—the use of derivatives involves costs, the risk that the value of derivatives may not correlate perfectly with their underlying assets, rates or indices, and the risk of mispricing or improper valuation. The use of derivatives may not succeed for various reasons, and the complexity and rapidly changing structure of derivatives markets may increase the possibility of market losses.

Emerging Markets Risk—investments in emerging markets are subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility.

Foreign Investment Risk—investments in foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investments in U.S. issuers and may result in greater price volatility.

High Portfolio Turnover Risk—higher portfolio turnover may adversely affect Fund performance by increasing Fund transaction costs and may increase a shareholder’s tax liability.

High Yield Risk—below investment grade debt securities and unrated securities of similar credit quality (commonly known as “junk bonds” or “high yield securities”) may be subject to greater levels of interest rate, credit, liquidity, and market risk than higher-rated securities. These securities are considered predominately speculative with respect to the issuer’s continuing ability to make principal and interest payments.

Interest Rate Risk—fixed coupon payments (cash flows) of bonds and debt securities may become less competitive with the market in periods of rising interest rates and cause bond prices to decline. During periods of increasing interest rates, the Fund may experience high levels of volatility and shareholder redemptions, and may have to sell securities at times when it would otherwise not do so, and at unfavorable prices, which could reduce the returns of the Fund.

Inverse Floating Rate Securities Risk— inverse floating rate securities (“inverse floaters”) are derivative debt instruments that pay interest at rates that generally vary inversely with specified short-term interest rates, meaning the interest payment received on inverse floaters generally will decrease when short-term interest rates increase. Inverse floaters are derivatives that involve leverage and will typically experience greater price volatility than a fixed-rate obligation of similar credit quality, which could magnify the Fund’s gains or losses. The markets for inverse floaters may be less developed and have less liquidity and inverse floaters have greater interest rate risk than more traditional fixed income securities.

Investment Company Risk—the risks of investing in other investment companies, including ETFs, open-end funds and closed-end funds, typically reflect the risks of the types of securities in which those investment companies invest. The market value returns of closed-end funds and ETFs may lag their returns at net asset value. When the Fund invests in another investment company, shareholders of the Fund bear their proportionate share of the other investment company’s fees and expenses as well as their share of the Fund’s fees and expenses.

Liquidity Risk—the Fund may not be able to dispose of particular investments, such as illiquid securities, readily at favorable times or prices or the Fund may have to sell them at a loss.

Management Risk—because the Fund is an actively managed investment portfolio, security selection or focus on securities in a particular style, market sector or group of companies may cause the Fund to incur losses or underperform relative to its benchmarks or other funds with a similar investment objective. There can be no guarantee that the Subadviser’s investment techniques and risk analysis will produce the desired result.

Municipal Market Risk—factors unique to the municipal bond market may negatively affect the value of municipal bonds.

Policy Risk— The withdrawal of U.S. and other government support to stabilize and support financial markets, including an increase in interest rates in the U.S. or elsewhere, or investor perceptions that this support may be withdrawn, could cause an increase in volatility in certain financial markets or constrict the availability of credit and liquidity, which could adversely affect the value and liquidity of certain securities.

Rule 144A Securities Risk— Investing in Rule 144A securities may reduce the liquidity of the Fund’s investments in the event that an adequate trading market does not exist for these securities. An insufficient number of qualified institutional buyers interested in purchasing Rule 144A securities at a particular time could adversely affect the marketability of the securities, and the Fund may be unable to sell the security at the desired time or price, if at all. The purchase price and subsequent valuation of Rule 144A securities normally reflect a discount, which may be significant, from the market price of comparable unrestricted securities for which a liquid trading market exists.

Senior Loans Risk— senior loans are typically not rated by a rating agency, registered with the Securities and Exchange Commission or any state securities commission or listed on any national securities exchange. Therefore, there may be less publicly available information about them than for registered or exchange-listed securities. An economic downturn generally leads to a higher delinquency rate, and a senior loan may lose significant value before a default occurs. In addition, any specific collateral used to secure a senior loan may decline in value or become illiquid, which would adversely affect the senior loan’s value. There can be no assurance that liquidation of such collateral would satisfy in full the borrower’s obligation in the event of non-payment of scheduled interest or principal or that such collateral could be readily liquidated. No active trading market may exist for certain senior loans, which may impair the ability of a fund to realize full value in the event of the need to sell a senior loan and which may make it difficult to value senior loans.

U.S. Government Securities Risk—obligations issued by some U.S. Government agencies, authorities, instrumentalities, or sponsored enterprises such as Government National Mortgage Association (“GNMA”), are backed by the full faith and credit of the U.S. Government, while obligations issued by others, such as Federal National Mortgage Association (“FNMA”), Federal Home Loan Mortgage Corporation (“FHLMC”), and Federal Home Loan Banks (“FHLBs”) are not backed by the full faith and credit of the U.S. Government and are backed solely by the entity’s own resources or by the ability of the entity to borrow from the U.S. Treasury. If one of these agencies defaults on a loan, there is no guarantee that the U.S. Government will provide financial support.

<b>PERFORMANCE</b>

The following performance information illustrates 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 performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. To obtain updated performance information please visit www.amgfunds.com or call 800.548.4539.

Calendar Year Total Returns as of 12/31/18 (Class N)

Best Quarter: 3.06% (3rd Quarter 2012)
Worst Quarter: -3.06% (2nd Quarter 2013)

Average Annual Total Returns as of 12/31/18

Average Annual Total Returns - AMG Managers DoubleLine Core Plus Bond Fund	1 Year	5 Years	Since Inception		Inception Date
Class N	(0.48%)	2.97%	3.87%	[1]	Jul. 18, 2011
Class N | Return After Taxes on Distributions	(1.78%)	1.54%	2.43%	[1]	Jul. 18, 2011
Class N | Return After Taxes on Distributions and Sale of Fund Shares	(0.28%)	1.63%	2.36%	[1]	Jul. 18, 2011
Class N | Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)	0.01%	2.52%	2.50%	[1]	Jul. 18, 2011
Class I	(0.32%)	3.23%	4.12%	[1]	Jul. 18, 2011
Class I | Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)	0.01%	2.52%	2.50%	[1]	Jul. 18, 2011
Class Z	(0.24%)		0.17%	[2]	Sep. 29, 2017
Class Z | Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)	0.01%		0.32%	[2]	Sep. 29, 2017

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). After-tax returns are shown for Class N shares only, and after-tax returns for Class I and Class Z shares will vary.

[1] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of this Prospectus, which reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired fund.

[2] AMG Funds LLC (the “Investment Manager”) has contractually agreed, through at least March 1, 2020, to waive management fees and/or pay or reimburse the Fund’s expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts and in connection with securities sold short), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, dividends payable with respect to securities sold short, acquired fund fees and expenses, and extraordinary expenses) of the Fund to the annual rate of 0.61% of the Fund’s average daily net assets (this annual rate or such other annual rate that may be in effect from time to time, the “Expense Cap”), subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months after the date any amounts are paid, waived or reimbursed by the Investment Manager, the Investment Manager may recover such amounts from the Fund, provided that such repayment would not cause the Fund’s Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of the items noted in the parenthetical above) to exceed either (i) the Expense Cap in effect at the time such amounts were paid, waived or reimbursed, or (ii) the Expense Cap in effect at the time of such repayment by the Fund. The contractual expense limitation may only be terminated in the event the Investment Manager or a successor ceases to be the investment manager of the Fund or a successor fund, by mutual agreement between the Investment Manager and the AMG Funds IV Board of Trustees or in the event of the Fund’s liquidation unless the Fund is reorganized or is a party to a merger in which the surviving entity is successor to the accounting and performance information of the Fund.

[1] Class N, Class I and Index performance shown reflects performance since the inception date of the Fund’s Class N and Class I shares on July 18, 2011.

[2] Class Z and Index performance shown reflects performance since the inception date of the Fund’s Class Z shares on September 29, 2017.