<SEC-DOCUMENT>0001576427-17-000123.txt : 20170629
<SEC-HEADER>0001576427-17-000123.hdr.sgml : 20170629
<ACCEPTANCE-DATETIME>20170629160625
ACCESSION NUMBER:		0001576427-17-000123
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170627
FILED AS OF DATE:		20170629
DATE AS OF CHANGE:		20170629

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Criteo S.A.
		CENTRAL INDEX KEY:			0001576427
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ADVERTISING AGENCIES [7311]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			I0
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		32 RUE BLANCHE
		CITY:			PARIS
		STATE:			I0
		ZIP:			75009
		BUSINESS PHONE:		33140402290

	MAIL ADDRESS:	
		STREET 1:		32 RUE BLANCHE
		CITY:			PARIS
		STATE:			I0
		ZIP:			75009

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Eichmann Eric
		CENTRAL INDEX KEY:			0001454782

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36153
		FILM NUMBER:		17938368

	MAIL ADDRESS:	
		STREET 1:		C/O CRITEO LEGAL DEPT.
		STREET 2:		387 PARK AVENUE SOUTH, 11TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10016
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_149876677205639.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-06-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001576427</issuerCik>
        <issuerName>Criteo S.A.</issuerName>
        <issuerTradingSymbol>CRTO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001454782</rptOwnerCik>
            <rptOwnerName>Eichmann Eric</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CRITEO LEGAL DEPT.</rptOwnerStreet1>
            <rptOwnerStreet2>387 PARK AVENUE SOUTH, 12TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10016</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>48.61</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-06-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>131000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-06-27</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>131000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>131000</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The exercise price of the stock option is 43.45 euros. The U.S. dollar equivalent of the exercise price is $48.61 using the European Central Bank (Close of Business) rate for June 26, 2017 (1.00 = $1.1187).</footnote>
        <footnote id="F2">Stock option granted on June 27, 2017. One-fourth of the grant will vest on the first anniversary of the grant date and an additional 1/16th of the grant vests quarterly thereafter, subject to continued service through each vesting date.</footnote>
        <footnote id="F3">The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share.</footnote>
        <footnote id="F4">For more information about the equity of the issuer held by the reporting person, please see the issuer's most recent definitive proxy statement filed with the Securities and Exchange Commission.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Nicole Kelsey, as attorney-in-fact for Eric Eichmann</signatureName>
        <signatureDate>2017-06-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
