<SEC-DOCUMENT>0000764065-21-000153.txt : 20210430
<SEC-HEADER>0000764065-21-000153.hdr.sgml : 20210430
<ACCEPTANCE-DATETIME>20210430163011
ACCESSION NUMBER:		0000764065-21-000153
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210428
FILED AS OF DATE:		20210430
DATE AS OF CHANGE:		20210430

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GREEN SUSAN MIRANDA
		CENTRAL INDEX KEY:			0001407047

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08944
		FILM NUMBER:		21878602

	MAIL ADDRESS:	
		STREET 1:		11211 LANDY COURT
		CITY:			KENSINGTON
		STATE:			MD
		ZIP:			20895

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_161981457727960.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-04-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001407047</rptOwnerCik>
            <rptOwnerName>GREEN SUSAN MIRANDA</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 PUBLIC SQUARE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CLEVELAND</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44114-2315</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2021-04-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6539</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>109082.3438</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Reflects the number of restricted shares granted to the Reporting Person as  the 2021 Director Restricted Shares pursuant to the Cleveland-Cliffs Inc. 2021 Nonemployee Directors' Compensation Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James D. Graham by Power of Attorney</signatureName>
        <signatureDate>2021-04-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
