<SEC-DOCUMENT>0000913760-20-000140.txt : 20200813
<SEC-HEADER>0000913760-20-000140.hdr.sgml : 20200813
<ACCEPTANCE-DATETIME>20200813164243
ACCESSION NUMBER:		0000913760-20-000140
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200811
FILED AS OF DATE:		20200813
DATE AS OF CHANGE:		20200813

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Harrod Patricia Marie
		CENTRAL INDEX KEY:			0001662208

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36045
		FILM NUMBER:		201099902

	MAIL ADDRESS:	
		STREET 1:		1251 NW BRIARCLIFF PARKWAY
		STREET 2:		SUITE 800
		CITY:			KANSAS CITY
		STATE:			MO
		ZIP:			64116

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			StoneX Group Inc.
		CENTRAL INDEX KEY:			0000913760
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY & COMMODITY BROKERS, DEALERS, EXCHANGES & SERVICES [6200]
		IRS NUMBER:				592921318
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		155 EAST 44TH STREET
		STREET 2:		SUITE 900
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		212-485-3500

	MAIL ADDRESS:	
		STREET 1:		155 EAST 44TH STREET
		STREET 2:		SUITE 900
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTL FCSTONE INC.
		DATE OF NAME CHANGE:	20110302

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERNATIONAL ASSETS HOLDING CORP
		DATE OF NAME CHANGE:	19931020
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_159735134901411.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-08-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000913760</issuerCik>
        <issuerName>StoneX Group Inc.</issuerName>
        <issuerTradingSymbol>SNEX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001662208</rptOwnerCik>
            <rptOwnerName>Harrod Patricia Marie</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1251 NW BRIARCLIFF PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 800</rptOwnerStreet2>
            <rptOwnerCity>KANSAS CITY</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>64116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Chief Risk Officer</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-08-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2863</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>59.2418</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11134</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported represents an average price.  The Reporting Person will provide to the Commission, the issuer and any stockholder, upon request, full information regarding the number of shares sold at each separate price.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Patricia M. Harrod</signatureName>
        <signatureDate>2020-08-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
