<SEC-DOCUMENT>0000887343-24-000213.txt : 20240514
<SEC-HEADER>0000887343-24-000213.hdr.sgml : 20240514
<ACCEPTANCE-DATETIME>20240514174033
ACCESSION NUMBER:		0000887343-24-000213
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240510
FILED AS OF DATE:		20240514
DATE AS OF CHANGE:		20240514

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MACHUCA LUIS
		CENTRAL INDEX KEY:			0001133099
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20288
		FILM NUMBER:		24946073

	MAIL ADDRESS:	
		STREET 1:		ITXC CORP
		STREET 2:		14600 NW GREENBRIER PARKWAY
		CITY:			BEAVERTON
		STATE:			OR
		ZIP:			97006

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COLUMBIA BANKING SYSTEM, INC.
		CENTRAL INDEX KEY:			0000887343
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		ORGANIZATION NAME:           	02 Finance
		IRS NUMBER:				911422237
		STATE OF INCORPORATION:			WA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1301 A STREET
		CITY:			TACOMA
		STATE:			WA
		ZIP:			98402
		BUSINESS PHONE:		2533051900

	MAIL ADDRESS:	
		STREET 1:		1301 A STREET
		CITY:			TACOMA
		STATE:			WA
		ZIP:			98402

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COLUMBIA BANKING SYSTEM INC
		DATE OF NAME CHANGE:	19930328
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1715722819.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-05-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000887343</issuerCik>
        <issuerName>COLUMBIA BANKING SYSTEM, INC.</issuerName>
        <issuerTradingSymbol>COLB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001133099</rptOwnerCik>
            <rptOwnerName>MACHUCA LUIS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O COLUMBIA BANKING SYSTEM, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 2156, MS 3100</rptOwnerStreet2>
            <rptOwnerCity>TACOMA</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98401-2156</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-05-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4183</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>22622</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">42,849 of the 61,288 shares previously reported as directly held by the reporting person are in respect of deferred compensation plan obligations that were previously inadvertently disclosed as held directly by the reporting person. The reporting person directly holds 22,622 shares of Common Stock and holds 42,849 shares of Deferred Compensation Phantom Stock in the Registrant's deferred compensation plan. Such Deferred Compensation Phantom Stock shall be paid in accordance with the terms of the deferred compensation plan following the end of the reporting person's employment with the Registrant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Lisa M. White, Attorney-in-fact</signatureName>
        <signatureDate>2024-05-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
