<SEC-DOCUMENT>0000352541-21-000024.txt : 20210222
<SEC-HEADER>0000352541-21-000024.hdr.sgml : 20210222
<ACCEPTANCE-DATETIME>20210222141719
ACCESSION NUMBER:		0000352541-21-000024
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20210218
FILED AS OF DATE:		20210222
DATE AS OF CHANGE:		20210222

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LARSEN JOHN O
		CENTRAL INDEX KEY:			0001483963

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09894
		FILM NUMBER:		21659521

	MAIL ADDRESS:	
		STREET 1:		P O BOX 14720
		CITY:			MADISON
		STATE:			WI
		ZIP:			53708-0720

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLIANT ENERGY CORP
		CENTRAL INDEX KEY:			0000352541
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				391380265
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4902 NORTH BILTMORE LANE
		STREET 2:		SUITE 1000
		CITY:			MADISON
		STATE:			WI
		ZIP:			53718-2148
		BUSINESS PHONE:		608-458-3311

	MAIL ADDRESS:	
		STREET 1:		4902 NORTH BILTMORE LANE
		STREET 2:		SUITE 1000
		CITY:			MADISON
		STATE:			WI
		ZIP:			53718-2148

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERSTATE ENERGY CORP
		DATE OF NAME CHANGE:	19980427

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WPL HOLDINGS INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161402141371927.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-02-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000352541</issuerCik>
        <issuerName>ALLIANT ENERGY CORP</issuerName>
        <issuerTradingSymbol>LNT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001483963</rptOwnerCik>
            <rptOwnerName>LARSEN JOHN O</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALLIANT ENERGY CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 14720</rptOwnerStreet2>
            <rptOwnerCity>MADISON</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53708-0720</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, Chairman and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>13628</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>76423.389</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>23722</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>100145.389</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10166.184</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Includes adjustments for accrued dividends, pursuant to a dividend reinvestment transaction exempt from Section 16 under Rule 16a-11.</footnote>
        <footnote id="F2">Represents restricted stock units (RSUs) which are converted to common stock on a one-to-one basis when vested. The RSUs vest on December 31, 2023.</footnote>
        <footnote id="F3">Reflects 401(k) holdings as of this filing date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jake C. Blavat, Attorney-in-Fact</signatureName>
        <signatureDate>2021-02-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>poa_larsenx022021.htm
<DESCRIPTION>POWER OF ATTORNEY LARSEN 2021
<TEXT>
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<pre>
POWER OF ATTORNEY



  KNOW ALL PERSONS BY THESE PRESENTS, that I appoint each of James H. Gallegos and Jake C. Blavat as my true and lawful agents and attorneys-in-fact with respect to all matters arising in connection with the my reporting obligations under Section 16(a) of the Securities Exchange Act of 1934 (the "Exchange Act") as amended, and related rules and regulations, with full power and authority to execute and deliver for and on my behalf all Securities and Exchange Commission Forms 3, 4, 5 and other documents in connection therewith regarding Alliant Energy Corporation, Interstate Power and Light Company, and Wisconsin Power and Light Company (collectively, the "Company") securities, as each of said agents and attorneys-in-fact may deem advisable.  I hereby give each of the named agents and attorneys-in-fact full power and authority to act in the premises, and hereby ratifies and confirms all that each of said agents and attorneys-in-fact may do by virtue hereof.


  I acknowledge that each attorney-in-fact, in serving in such capacity at my request, is not assuming any of my responsibilities to comply with the Exchange Act.  I agree to defend and hold harmless each attorney-in-fact from and against any and all loss, damage or liability that such attorney-in-fact may sustain as a result of any action taken in good faith hereunder.

  This Power of Attorney shall remain in full force and effect until I am no longer required to file documents with respect to my holdings of and transactions in securities issued by the Company, unless earlier revoked by me in writing or by executing a new Power of Attorney.

    IN WITNESS WHEREOF, I have executed this Power of Attorney on this 9thday of February, 2021.


                            /s/ John O. Larsen
                            John O. Larsen
        Exhibit 24


</pre>
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</SEC-DOCUMENT>
