<SEC-DOCUMENT>0001127602-23-011576.txt : 20230329
<SEC-HEADER>0001127602-23-011576.hdr.sgml : 20230329
<ACCEPTANCE-DATETIME>20230329180124
ACCESSION NUMBER:		0001127602-23-011576
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230327
FILED AS OF DATE:		20230329
DATE AS OF CHANGE:		20230329

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Luhrs Michael
		CENTRAL INDEX KEY:			0001921786

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16189
		FILM NUMBER:		23776453

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

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NISOURCE INC.
		CENTRAL INDEX KEY:			0001111711
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				352108964
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		801 EAST 86TH AVE
		CITY:			MERRILLVILLE
		STATE:			IN
		ZIP:			46410-6272
		BUSINESS PHONE:		2196475200

	MAIL ADDRESS:	
		STREET 1:		801 EAST 86TH AVE
		CITY:			MERRILLVILLE
		STATE:			IN
		ZIP:			46410-6272

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NISOURCE INC/DE
		DATE OF NAME CHANGE:	20001103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NEW NISOURCE INC
		DATE OF NAME CHANGE:	20000412
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>form4a.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0407</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2023-03-27</periodOfReport>

    <dateOfOriginalSubmission>2023-03-28</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001111711</issuerCik>
        <issuerName>NISOURCE INC.</issuerName>
        <issuerTradingSymbol>NI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001921786</rptOwnerCik>
            <rptOwnerName>Luhrs Michael</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>801 E. 86TH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MERRILLVILLE</rptOwnerCity>
            <rptOwnerState>IN</rptOwnerState>
            <rptOwnerZipCode>46410</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>EVP, Strategy &amp; Risk &amp; CCO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-03-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8133</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8133</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Amends the number of Restricted Stock Units (&quot;RSUs&quot;) reported on the reporting person's Form 4 filed on March 28, 2023.  Due to an administrative error the number of RSUs reported on the reporting person's Form 4 filed on March 28, 2023 was underreported by 739 shares.  Each RSU represents a contingent right to receive one share of the Company's common stock pursuant to the NiSource Inc. 2020 Omnibus Incentive Plan.  Subject to certain forfeiture conditions, the RSUs will 100% vest on March 27, 2026 provided the officer is continuously employed by the Company through and including that date.  After considering this revision, the beneficial ownership total in column 5 is 19,224 shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kimberly S. Cuccia, Attorney-in-Fact</signatureName>
        <signatureDate>2023-03-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
