<SEC-DOCUMENT>0001006837-18-000123.txt : 20181003
<SEC-HEADER>0001006837-18-000123.hdr.sgml : 20181003
<ACCEPTANCE-DATETIME>20181003163046
ACCESSION NUMBER:		0001006837-18-000123
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180911
FILED AS OF DATE:		20181003
DATE AS OF CHANGE:		20181003

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FALCONE PHILIP
		CENTRAL INDEX KEY:			0001233569

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35210
		FILM NUMBER:		181105412

	MAIL ADDRESS:	
		STREET 1:		450 PARK AVENUE, 30TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HC2 HOLDINGS, INC.
		CENTRAL INDEX KEY:			0001006837
		STANDARD INDUSTRIAL CLASSIFICATION:	FABRICATED STRUCTURAL METAL PRODUCTS [3440]
		IRS NUMBER:				541708481
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		450 PARK AVENUE
		STREET 2:		30TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		212-235-2690

	MAIL ADDRESS:	
		STREET 1:		450 PARK AVENUE
		STREET 2:		30TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HC2 Holdings, Inc.
		DATE OF NAME CHANGE:	20140415

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PTGi HOLDING, INC.
		DATE OF NAME CHANGE:	20131108

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PRIMUS TELECOMMUNICATIONS GROUP INC
		DATE OF NAME CHANGE:	19960814
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>wf-form4a_153859863040528.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2018-09-11</periodOfReport>

    <dateOfOriginalSubmission>2018-09-13</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001006837</issuerCik>
        <issuerName>HC2 HOLDINGS, INC.</issuerName>
        <issuerTradingSymbol>HCHC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001233569</rptOwnerCik>
            <rptOwnerName>FALCONE PHILIP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>450 PARK AVENUE, 30TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock option (Right To Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.05</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-09-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>150000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-05-20</value>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>150000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>84608</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock option (Right To Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.02</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-09-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>21795</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-05-20</value>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>21795.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>28452</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Option vested and became exercisable in three equal annual installments beginning on October 28, 2014.</footnote>
        <footnote id="F2">The Form 4 filed by reporting person on September 13, 2018 reported that the option expiration date noted on the original Form 4 filed on October 30, 2014 (the &quot;Original Form 4&quot;) for the option listed was incorrect.  This amended Form 4 is being filed to clarify that, in fact, the expiration date applicable to this option is May 20, 2024, as properly reported in the Original Form 4.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Philip Falcone</signatureName>
        <signatureDate>2018-10-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
