<SEC-DOCUMENT>0000764065-21-000090.txt : 20210305
<SEC-HEADER>0000764065-21-000090.hdr.sgml : 20210305
<ACCEPTANCE-DATETIME>20210305123040
ACCESSION NUMBER:		0000764065-21-000090
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210305
FILED AS OF DATE:		20210305
DATE AS OF CHANGE:		20210305

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Koci Keith
		CENTRAL INDEX KEY:			0001316514

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08944
		FILM NUMBER:		21717476

	MAIL ADDRESS:	
		STREET 1:		ONE RIVERWAY
		STREET 2:		SUITE 1100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CLEVELAND-CLIFFS INC.
		CENTRAL INDEX KEY:			0000764065
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
		IRS NUMBER:				341464672
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 PUBLIC SQUARE
		STREET 2:		STE. 3300
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44114-2315
		BUSINESS PHONE:		216-694-5700

	MAIL ADDRESS:	
		STREET 1:		200 PUBLIC SQUARE
		STREET 2:		STE. 3300
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44114-2315

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CLIFFS NATURAL RESOURCES INC.
		DATE OF NAME CHANGE:	20081015

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CLEVELAND CLIFFS INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161496542501654.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-03-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000764065</issuerCik>
        <issuerName>CLEVELAND-CLIFFS INC.</issuerName>
        <issuerTradingSymbol>CLF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001316514</rptOwnerCik>
            <rptOwnerName>Koci Keith</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 PUBLIC SQUARE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CLEVELAND</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44114</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2021-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>13.449</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>210033</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in column four is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $13.44 to $13.45, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer or the Staff of the Securities and Exchange Commission, upon request, with full information regarding the number of shares purchased at each separate price within this range.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James D. Graham, By Power of Attorney</signatureName>
        <signatureDate>2021-03-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
