<SEC-DOCUMENT>0001467858-20-000018.txt : 20200103
<SEC-HEADER>0001467858-20-000018.hdr.sgml : 20200103
<ACCEPTANCE-DATETIME>20200103165848
ACCESSION NUMBER:		0001467858-20-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20191231
FILED AS OF DATE:		20200103
DATE AS OF CHANGE:		20200103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Stephenson Carol
		CENTRAL INDEX KEY:			0001493255

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34960
		FILM NUMBER:		20506443

	MAIL ADDRESS:	
		STREET 1:		300 RENAISSANCE CENTER
		STREET 2:		M/C:482-C25-A36
		CITY:			DETROIT
		STATE:			MI
		ZIP:			48265-3000

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			General Motors Co
		CENTRAL INDEX KEY:			0001467858
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR VEHICLES & PASSENGER CAR BODIES [3711]
		IRS NUMBER:				270756180
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		300 RENAISSANCE CENTER
		CITY:			DETROIT
		STATE:			MI
		ZIP:			48265-3000
		BUSINESS PHONE:		313.667.1500

	MAIL ADDRESS:	
		STREET 1:		300 RENAISSANCE CENTER
		CITY:			DETROIT
		STATE:			MI
		ZIP:			48265-3000
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_157808870835317.xml
<DESCRIPTION>FORM 4
<TEXT>
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<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001467858</issuerCik>
        <issuerName>General Motors Co</issuerName>
        <issuerTradingSymbol>GM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001493255</rptOwnerCik>
            <rptOwnerName>Stephenson Carol</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>300 RENAISSANCE CENTER</rptOwnerStreet1>
            <rptOwnerStreet2>M/C: 482-C24-A68</rptOwnerStreet2>
            <rptOwnerCity>DETROIT</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>48265-3000</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Share Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.0</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5957</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5957.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>65274</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Share Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
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                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2624</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
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            <exerciseDate>
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            <expirationDate>
                <footnoteId id="F2"/>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
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            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>67898</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Deferred share units of the Company's Common Stock (&quot;DSUs&quot;) were awarded on December 31, 2019, pursuant to the General Motors Company Deferred Compensation Plan (the &quot;Plan&quot;) for Non-Employee Directors. Each non-employee director is required to defer one-half of the $285,000 annual retainer fee for service on the Board of Directors into DSUs and may elect to defer more. The deferred portion of the retainer fee is converted to DSUs based on the average closing price of the Company's Common Stock during the previous calendar year, which was $37.56 in 2019. Amounts credited as DSUs will be paid in cash after the director leaves the Board, valued at the average closing price of the Company's Common Stock during the quarter immediately preceding payment.</footnote>
        <footnote id="F2">Represents dividends accrued on DSUs in 2019 that were credited as additional DSUs at the end of the year pursuant to the terms of the Plan.   The dividends were converted to DSUs based on the average of the high and low trading price of the Company's Common Stock on the applicable quarterly dividend payment date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Tia Y. Turk, Attorney-In-Fact for Ms. Stephenson</signatureName>
        <signatureDate>2020-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
