<SEC-DOCUMENT>0001127602-20-007835.txt : 20200226
<SEC-HEADER>0001127602-20-007835.hdr.sgml : 20200226
<ACCEPTANCE-DATETIME>20200226082146
ACCESSION NUMBER:		0001127602-20-007835
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200224
FILED AS OF DATE:		20200226
DATE AS OF CHANGE:		20200226

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Byrne Samuel T
		CENTRAL INDEX KEY:			0001474915

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13459
		FILM NUMBER:		20653370

	MAIL ADDRESS:	
		STREET 1:		CROSSHARBOR CAPITAL PARTNERS
		STREET 2:		ONE BOSTON PLACE, SUITE 2300
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02108

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AFFILIATED MANAGERS GROUP, INC.
		CENTRAL INDEX KEY:			0001004434
		STANDARD INDUSTRIAL CLASSIFICATION:	INVESTMENT ADVICE [6282]
		IRS NUMBER:				043218510
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		777 SOUTH FLAGLER DRIVE
		STREET 2:		SUITE 1201 EAST TOWER
		CITY:			WEST PALM BEACH
		STATE:			FL
		ZIP:			33401
		BUSINESS PHONE:		(800) 345-1100

	MAIL ADDRESS:	
		STREET 1:		777 SOUTH FLAGLER DRIVE
		STREET 2:		SUITE 1201 EAST TOWER
		CITY:			WEST PALM BEACH
		STATE:			FL
		ZIP:			33401

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AFFILIATED MANAGERS GROUP INC
		DATE OF NAME CHANGE:	19970822
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-02-24</periodOfReport>

    <issuer>
        <issuerCik>0001004434</issuerCik>
        <issuerName>AFFILIATED MANAGERS GROUP, INC.</issuerName>
        <issuerTradingSymbol>AMG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001474915</rptOwnerCik>
            <rptOwnerName>Byrne Samuel T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AFFILIATED MANAGERS GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>777 SOUTH FLAGLER DRIVE</rptOwnerStreet2>
            <rptOwnerCity>WEST PALM BEACH</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33401</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-02-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4054</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>85.10</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27146</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-02-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>946</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>85.26</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>28092</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The price reflects the weighted average price of shares purchased on the open market. On February 24, 2020, the individual transaction prices ranged from $84.99 to $85.15, and on February 25, 2020, the individual transaction prices ranged from $85.12 to $85.30. Specific transaction details will be provided to the SEC upon request.</footnote>
        <footnote id="F2">Includes nine shares of common stock acquired as a result of dividend accruals on previously vested restricted stock unit awards.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ David M. Billings, Attorney-in-Fact</signatureName>
        <signatureDate>2020-02-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
