<SEC-DOCUMENT>0000811156-21-000056.txt : 20210806
<SEC-HEADER>0000811156-21-000056.hdr.sgml : 20210806
<ACCEPTANCE-DATETIME>20210806122826
ACCESSION NUMBER:		0000811156-21-000056
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210805
FILED AS OF DATE:		20210806
DATE AS OF CHANGE:		20210806

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hendrian Catherine A
		CENTRAL INDEX KEY:			0001701746

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09513
		FILM NUMBER:		211151985

	MAIL ADDRESS:	
		STREET 1:		ONE ENERGY PLAZA
		CITY:			JACKSON
		STATE:			MI
		ZIP:			49201

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CMS ENERGY CORP
		CENTRAL INDEX KEY:			0000811156
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				382726431
		STATE OF INCORPORATION:			MI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE ENERGY PLAZA
		CITY:			JACKSON
		STATE:			MI
		ZIP:			49201
		BUSINESS PHONE:		5177880550

	MAIL ADDRESS:	
		STREET 1:		ONE ENERGY PLAZA
		CITY:			JACKSON
		STATE:			MI
		ZIP:			49201
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_162826729200231.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-08-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000811156</issuerCik>
        <issuerName>CMS ENERGY CORP</issuerName>
        <issuerTradingSymbol>CMS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001701746</rptOwnerCik>
            <rptOwnerName>Hendrian Catherine A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE ENERGY PLAZA</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>JACKSON</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>49201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-08-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7991</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>62.7975</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>43856</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The total holdings reflect an adjustment of 192 additional shares of Common Stock of CMS Energy Corporation (&quot;CMS&quot;) acquired as a result of dividend reinvestment pursuant to the reporting person's participation in the CMS Stock Purchase Plan, and an adjustment of 164 additional shares of Restricted Stock purchased on behalf of the reporting person as a result of an automatic acquisition of Restricted Stock in lieu of cash dividends pursuant to the terms of the award granted to the reporting person in accordance with the provisions of the CMS Performance Incentive Stock Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Rhonda M. Morris, Attny-in-Fact</signatureName>
        <signatureDate>2021-08-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
