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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 ZHvhmXPJUjEFnqCcRKqr0w==

<SEC-DOCUMENT>0001269847-07-000045.txt : 20071221
<SEC-HEADER>0001269847-07-000045.hdr.sgml : 20071221
<ACCEPTANCE-DATETIME>20071221110924
ACCESSION NUMBER:		0001269847-07-000045
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20071220
FILED AS OF DATE:		20071221
DATE AS OF CHANGE:		20071221

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACI WORLDWIDE, INC.
		CENTRAL INDEX KEY:			0000935036
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				470772104
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		120 BROADWAY, SUITE 3350
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10271
		BUSINESS PHONE:		402-390-7600

	MAIL ADDRESS:	
		STREET 1:		120 BROADWAY, SUITE 3350
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10271

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TRANSACTION SYSTEMS ARCHITECTS INC
		DATE OF NAME CHANGE:	19950109

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HEASLEY PHILIP G
		CENTRAL INDEX KEY:			0001078558

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25346
		FILM NUMBER:		071321353

	BUSINESS ADDRESS:	
		STREET 1:		CHICAGO TITLE CORP
		STREET 2:		171 N CLARK ST
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60601
		BUSINESS PHONE:		4023907600

	MAIL ADDRESS:	
		STREET 1:		TRANSACTION SYSTEMS ARCHITECTS, INC.
		STREET 2:		224 SOUTH 108 AVENUE
		CITY:			OMAHA
		STATE:			NE
		ZIP:			68154
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-12-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000935036</issuerCik>
        <issuerName>ACI WORLDWIDE, INC.</issuerName>
        <issuerTradingSymbol>ACIW</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001078558</rptOwnerCik>
            <rptOwnerName>HEASLEY PHILIP G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>120 BROADWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3350</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10271</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO and President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-12-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.95</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>220685</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The purchase price ranged from $16.86 to $17.0098 with an average purchase price of $16.95.</footnote>
        <footnote id="F2">The amount of securities owned has also been updated to include 808 shares acquired under the ACI Worldwide, Inc. 1999 Employees Stock Purchase Plan on October 31, 2007.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Philip G. Heasley</signatureName>
        <signatureDate>2007-12-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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