<SEC-DOCUMENT>0001819846-26-000005.txt : 20260806
<SEC-HEADER>0001819846-26-000005.hdr.sgml : 20260806
<ACCEPTANCE-DATETIME>20260806165559
ACCESSION NUMBER:		0001819846-26-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260804
FILED AS OF DATE:		20260806
DATE AS OF CHANGE:		20260806

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Schurz Todd F.
		CENTRAL INDEX KEY:			0001819846
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-06233
		FILM NUMBER:		261250143

	MAIL ADDRESS:	
		STREET 1:		P O BOX 1602
		CITY:			SOUTH BEND
		STATE:			IN
		ZIP:			46634

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			1ST SOURCE CORP
		CENTRAL INDEX KEY:			0000034782
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		ORGANIZATION NAME:           	02 Finance
		EIN:				351068133
		STATE OF INCORPORATION:			IN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		100 NORTH MICHIGAN STREET
		CITY:			SOUTH BEND
		STATE:			IN
		ZIP:			46601
		BUSINESS PHONE:		5742352702

	MAIL ADDRESS:	
		STREET 1:		P O BOX 1602
		STREET 2:		P O BOX 1602
		CITY:			SOUTH BEND
		STATE:			IN
		ZIP:			46634

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FBT BANCORP INC
		DATE OF NAME CHANGE:	19820818
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1786049756.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-08-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000034782</issuerCik>
        <issuerName>1ST SOURCE CORP</issuerName>
        <issuerTradingSymbol>SRCE</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001819846</rptOwnerCik>
            <rptOwnerName>Schurz Todd F.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>P.O. BOX 1602</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SOUTH BEND</rptOwnerCity>
            <rptOwnerState>IN</rptOwnerState>
            <rptOwnerZipCode>46634</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-08-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>155</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>89.76</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15966</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Brian S. Duba, Attorney-in-Fact</signatureName>
        <signatureDate>2026-08-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
