    <SEC-DOCUMENT>0001104659-21-051276-index.html : 20210416
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    <ACCEPTANCE-DATETIME>20210416134024
    ACCESSION NUMBER:		0001104659-21-051276
    CONFORMED SUBMISSION TYPE:	DEF 14A
    PUBLIC DOCUMENT COUNT:		4
    CONFORMED PERIOD OF REPORT:	20210517
    FILED AS OF DATE:		20210416
    DATE AS OF CHANGE:		20210416

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			INTERNATIONAL BANCSHARES CORP
    		CENTRAL INDEX KEY:			0000315709
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		IRS NUMBER:				742157138
    		STATE OF INCORPORATION:			TX
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		DEF 14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-09439
    		FILM NUMBER:		21830978

    	BUSINESS ADDRESS:
    		STREET 1:		12OO SAN BERNARDO AVE
    		STREET 2:		PO BOX 1359
    		CITY:			LAREDO
    		STATE:			TX
    		ZIP:			78040-1359
    		BUSINESS PHONE:		9567227611

    	MAIL ADDRESS:
    		STREET 1:		P O BOX 1359
    		STREET 2:		1200 SAN BERNARDO
    		CITY:			LAREDO
    		STATE:			TX
    		ZIP:			78040
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEF 14A
    <SEQUENCE>1
    <FILENAME>tm219313-1_def14a.htm
    <DESCRIPTION>DEF 14A
    <TEXT>
    Document 1 - file: tm219313-1_def14a.htm

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    <SEQUENCE>2
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    <DESCRIPTION>GRAPHIC
    <TEXT>
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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
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    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: tm219313d1-pc_pg01proxybw.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
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    <DESCRIPTION>GRAPHIC
    <TEXT>
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