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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 VK1Ip2ct4A+aaRVoKN2bWHkKFIGssj94KSv6A9tkrYUI4NYhzuQSXKG0SVP+40/1
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<SEC-DOCUMENT>0001269847-08-000034.txt : 20080918
<SEC-HEADER>0001269847-08-000034.hdr.sgml : 20080918
<ACCEPTANCE-DATETIME>20080918165406
ACCESSION NUMBER:		0001269847-08-000034
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080916
FILED AS OF DATE:		20080918
DATE AS OF CHANGE:		20080918

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:			1231

	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:			BYRNES DENNIS
		CENTRAL INDEX KEY:			0001245179

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25346
		FILM NUMBER:		081078829

	BUSINESS ADDRESS:	
		STREET 1:		224 SOUTH 108TH AVENUE
		CITY:			OMAHA
		STATE:			NE
		ZIP:			68154
		BUSINESS PHONE:		402-390-7600

	MAIL ADDRESS:	
		STREET 1:		6060 COVENTRY DRIVE
		CITY:			ELKHORN
		STATE:			NE
		ZIP:			68022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-09-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001245179</rptOwnerCik>
            <rptOwnerName>BYRNES DENNIS</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>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP, General Counsel &amp; Sec</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-09-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18350</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.76</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>58060</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of restricted stock awarded on September 16, 2008 pursuant to the Company's 2005 Equity and Performance Incentive Plan, as amended.  The restrictions on these shares of restricted stock will generally lapse with respect to 25% of the shares on each anniversary of the grant date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Victoria H. Finley, Attorney in Fact  For: Dennis P. Byrnes</signatureName>
        <signatureDate>2008-09-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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