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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 NNnIbUF0xbGE4VLPU6IzAUKfmCI3sldItOGBFVlr0vbKZ3zOHrCN0ecdR1Z2bFh0
 sYhol/ql3N3AX2iiRZREtw==

<SEC-DOCUMENT>0001181431-06-031844.txt : 20060519
<SEC-HEADER>0001181431-06-031844.hdr.sgml : 20060519
<ACCEPTANCE-DATETIME>20060519174146
ACCESSION NUMBER:		0001181431-06-031844
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060515
FILED AS OF DATE:		20060519
DATE AS OF CHANGE:		20060519

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CASS INFORMATION SYSTEMS INC
		CENTRAL INDEX KEY:			0000708781
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-BUSINESS SERVICES, NEC [7389]
		IRS NUMBER:				431265338
		STATE OF INCORPORATION:			MO
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		13001 HOLLENBERG DR.
		CITY:			BRIDGETON
		STATE:			MO
		ZIP:			63044
		BUSINESS PHONE:		3145055500

	MAIL ADDRESS:	
		STREET 1:		13001 HOLLENBERG DR.
		CITY:			BRIDGETON
		STATE:			MO
		ZIP:			63044

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CASS COMMERCIAL CORP
		DATE OF NAME CHANGE:	19950518

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Appelbaum P Stephen
		CENTRAL INDEX KEY:			0001363586

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-44497
		FILM NUMBER:		06856339

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		314-506-5500

	MAIL ADDRESS:	
		STREET 1:		13001 HOLLENBERG DRIVE
		CITY:			BRIDGETON
		STATE:			MO
		ZIP:			63044
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>rrd118904.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-05-15</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000708781</issuerCik>
        <issuerName>CASS INFORMATION SYSTEMS INC</issuerName>
        <issuerTradingSymbol>CASS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001363586</rptOwnerCik>
            <rptOwnerName>Appelbaum P Stephen</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>13001 HOLLENBERG DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BRIDGETON</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63044</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>/s/ P Stephen Appelbaum</signatureName>
        <signatureDate>2006-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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