<SEC-DOCUMENT>0001002910-23-000049.txt : 20230213
<SEC-HEADER>0001002910-23-000049.hdr.sgml : 20230213
<ACCEPTANCE-DATETIME>20230213162752
ACCESSION NUMBER:		0001002910-23-000049
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230209
FILED AS OF DATE:		20230213
DATE AS OF CHANGE:		20230213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Singh Leonard P
		CENTRAL INDEX KEY:			0001936928

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14756
		FILM NUMBER:		23618921

	MAIL ADDRESS:	
		STREET 1:		1901 CHOUTEAU AVENUE
		STREET 2:		PO BOX 66149
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63166-6149

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMEREN CORP
		CENTRAL INDEX KEY:			0001002910
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				431723446
		STATE OF INCORPORATION:			MO
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1901 CHOUTEAU AVE
		STREET 2:		MC 1310
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63166-6149
		BUSINESS PHONE:		314-621-3222

	MAIL ADDRESS:	
		STREET 1:		1901 CHOUTEAU AVE
		STREET 2:		MC 1310
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63103
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_167632365351913.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-02-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001002910</issuerCik>
        <issuerName>AMEREN CORP</issuerName>
        <issuerTradingSymbol>AEE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001936928</rptOwnerCik>
            <rptOwnerName>Singh Leonard P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1901 CHOUTEAU AVENUE, MC 1310</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 66149</rptOwnerStreet2>
            <rptOwnerCity>ST LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63166-6149</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Chmn &amp; President of Subsidiary</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $.01 Par Value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>41</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 Par Value</value>
            </securityTitle>
            <transactionDate>
                <value>2023-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3683</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12076</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the estimated number of share equivalents held by the reporting person in the unitized stock fund included in the Ameren Corporation Savings Investment Plan as of January 31, 2023.</footnote>
        <footnote id="F2">These restricted stock units were granted under the issuer's 2022 Omnibus Incentive Compensation Plan (the &quot;Plan&quot;) and are scheduled to vest upon the payment date in 2025, which shall be no later than March 15, 2025, subject to the terms of the Plan and the applicable award agreement issued thereunder.</footnote>
        <footnote id="F3">Amount includes 109 accrued dividend equivalents acquired during the third through fourth quarters of 2022 pursuant to a dividend reinvestment feature of restricted stock units granted under the Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Jonathan T. Shade, Asst Secy. of Ameren Corporation, attorney-in-fact for Leonard P. Singh</signatureName>
        <signatureDate>2023-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
