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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 OT9m7hLLLOK8s/p69I1KHb4vRhWSHZmcwBNTenoJfnVmBplV30GfSFkfnWIfmUYQ
 GFb2Y2+xgjzkoSptCRLhgQ==

<SEC-DOCUMENT>0001269847-10-000018.txt : 20100920
<SEC-HEADER>0001269847-10-000018.hdr.sgml : 20100920
<ACCEPTANCE-DATETIME>20100920151110
ACCESSION NUMBER:		0001269847-10-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100916
FILED AS OF DATE:		20100920
DATE AS OF CHANGE:		20100920

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Morem David Neil
		CENTRAL INDEX KEY:			0001330346

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25346
		FILM NUMBER:		101080382

	MAIL ADDRESS:	
		STREET 1:		6060 COVENTRY DRIVE
		CITY:			ELKHORN
		STATE:			NE
		ZIP:			68022

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
</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>2010-09-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001330346</rptOwnerCik>
            <rptOwnerName>Morem David Neil</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, Global Business Operation</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-09-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1213</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.64</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46035</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares surrendered by the reporting person to pay the tax liability due upon the vesting of twenty-five percent (25%) of his restricted stock award.</footnote>
        <footnote id="F2">The amount of securities owned has also been updated to include 557 shares acquired under the Company's 1999 Employee Stock Purchase Plan, as amended.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Victoria H. Sitz, Attorney in Fact  For: David N. Morem</signatureName>
        <signatureDate>2010-09-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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