<SEC-DOCUMENT>0001002910-22-000069.txt : 20220707
<SEC-HEADER>0001002910-22-000069.hdr.sgml : 20220707
<ACCEPTANCE-DATETIME>20220707163421
ACCESSION NUMBER:		0001002910-22-000069
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220701
FILED AS OF DATE:		20220707
DATE AS OF CHANGE:		20220707

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:		221072005

	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_165722604782396.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2022-07-01</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>Chrmn and Pres-Elect of sub</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 Par Value</value>
            </securityTitle>
            <transactionDate>
                <value>2022-07-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6642</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6642</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 Par Value</value>
            </securityTitle>
            <transactionDate>
                <value>2022-07-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1642</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8284</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock units granted under the issuer's 2022 Omnibus Incentive Compensation Plan (the &quot;Plan&quot;), which will vest in equal installments on February 29, 2024, and February 28, 2025, subject to the terms of the Plan and the applicable award agreement issued thereunder.</footnote>
        <footnote id="F2">Represents restricted stock units granted under the Plan, which 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>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Jonathan T. Shade, Asst Secy. of Ameren Corporation, attorney-in-fact for Leonard P. Singh</signatureName>
        <signatureDate>2022-07-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
