<SEC-DOCUMENT>0000846913-16-000088.txt : 20160104
<SEC-HEADER>0000846913-16-000088.hdr.sgml : 20160104
<ACCEPTANCE-DATETIME>20160104162403
ACCESSION NUMBER:		0000846913-16-000088
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20151230
FILED AS OF DATE:		20160104
DATE AS OF CHANGE:		20160104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FUEL TECH, INC.
		CENTRAL INDEX KEY:			0000846913
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL & COMMERCIAL FANS & BLOWERS & AIR PURIFYING EQUIP [3564]
		IRS NUMBER:				205657551
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		27601 BELLA VISTA PARKWAY
		CITY:			WARRENVILLE
		STATE:			IL
		ZIP:			60555
		BUSINESS PHONE:		6308454433

	MAIL ADDRESS:	
		STREET 1:		27601 BELLA VISTA PARKWAY
		CITY:			WARRENVILLE
		STATE:			IL
		ZIP:			60555

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FUEL TECH N V
		DATE OF NAME CHANGE:	19930510

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ARNONE VINCENT J
		CENTRAL INDEX KEY:			0001272727

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33059
		FILM NUMBER:		161318384
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_145194263202612.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-12-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000846913</issuerCik>
        <issuerName>FUEL TECH, INC.</issuerName>
        <issuerTradingSymbol>FTEK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001272727</rptOwnerCik>
            <rptOwnerName>ARNONE VINCENT J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>27601 BELLA VISTA PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WARRENVILLE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60555</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-12-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.85</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>214440</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This transaction was executed in multiple trades at prices ranging from $1.82 to $1.85; the price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which the transactions were effected upon request to the SEC staff, the Registrant, or a security holder of the Registrant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Vincent J. Arnone</signatureName>
        <signatureDate>2016-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
