<SEC-DOCUMENT>0001645773-17-000019.txt : 20171031
<SEC-HEADER>0001645773-17-000019.hdr.sgml : 20171031
<ACCEPTANCE-DATETIME>20171031171852
ACCESSION NUMBER:		0001645773-17-000019
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171027
FILED AS OF DATE:		20171031
DATE AS OF CHANGE:		20171031

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Peck James M
		CENTRAL INDEX KEY:			0001645773

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37470
		FILM NUMBER:		171166590

	MAIL ADDRESS:	
		STREET 1:		C/O TRANSUNION
		STREET 2:		555 WEST ADAMS STREET
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60661

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TransUnion
		CENTRAL INDEX KEY:			0001552033
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-CONSUMER CREDIT REPORTING, COLLECTION AGENCIES [7320]
		IRS NUMBER:				611678417
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		555 WEST ADAMS STREET
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60661
		BUSINESS PHONE:		(312) 985-2000

	MAIL ADDRESS:	
		STREET 1:		555 WEST ADAMS STREET
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60661

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TransUnion Holding Company, Inc.
		DATE OF NAME CHANGE:	20120612
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150948471851779.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-10-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001552033</issuerCik>
        <issuerName>TransUnion</issuerName>
        <issuerTradingSymbol>TRU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001645773</rptOwnerCik>
            <rptOwnerName>Peck James M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TRANSUNION</rptOwnerStreet1>
            <rptOwnerStreet2>555 WEST ADAMS STREET</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60661</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-10-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>36970</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.99</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>239313</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-10-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18864</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>52.41</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>220449</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>395196</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By limited liability company</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.99</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-10-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>36970</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.99</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>36970.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1146081</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan.</footnote>
        <footnote id="F2">The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $51.72 to $52.92, inclusive. The reporting person undertakes to provide to TransUnion, any security holder of TransUnion, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F3">Represents an initial grant of 1,848,517 stock options, 40% of which vest upon the attainment of time-based vesting criteria and 60% of which vest upon the attainment of both time-based and performance-based vesting criteria. The performance-based vesting criteria was satisfied on February 22, 2017, and all options now follow the time-based vesting criteria as follows: 20% on the first anniversary of the date of grant and 5% on the last day of each subsequent full calendar quarter.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Michael J. Forde, by power of attorney</signatureName>
        <signatureDate>2017-10-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
