<SEC-DOCUMENT>0001127602-20-017991.txt : 20200527
<SEC-HEADER>0001127602-20-017991.hdr.sgml : 20200527
<ACCEPTANCE-DATETIME>20200527155230
ACCESSION NUMBER:		0001127602-20-017991
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200518
FILED AS OF DATE:		20200527
DATE AS OF CHANGE:		20200527

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Tavares Silvio
		CENTRAL INDEX KEY:			0001685787

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-27512
		FILM NUMBER:		20915157

	MAIL ADDRESS:	
		STREET 1:		20 TIPTOE LANE
		CITY:			BURLINGAME
		STATE:			CA
		ZIP:			94010

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CSG SYSTEMS INTERNATIONAL INC
		CENTRAL INDEX KEY:			0001005757
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROCESSING & DATA PREPARATION [7374]
		IRS NUMBER:				470783182
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6175 SOUTH WILLOW DRIVE
		CITY:			GREENWOOD VILLAGE
		STATE:			CO
		ZIP:			80111
		BUSINESS PHONE:		3037962850

	MAIL ADDRESS:	
		STREET 1:		6175 SOUTH WILLOW DRIVE
		CITY:			GREENWOOD VILLAGE
		STATE:			CO
		ZIP:			80111
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>form3.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2020-05-18</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001005757</issuerCik>
        <issuerName>CSG SYSTEMS INTERNATIONAL INC</issuerName>
        <issuerTradingSymbol>CSGS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001685787</rptOwnerCik>
            <rptOwnerName>Tavares Silvio</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6175 SOUTH WILLOW DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENWOOD VILLAGE</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Silvio Tavares</signatureName>
        <signatureDate>2020-05-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
