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Exhibit 21

List of Subsidiaries

Subsidiaries of International Bancshares Corporation

Name	State of Incorporation or Organization	Business	% of Ownership
IBC Subsidiary Corporation	Delaware	Bank Holding Company		100	%
IBC Life Insurance Company	Texas	Credit Life Insurance		100	%
IBC Trading Company	Texas	Export Trading		100	%
IBC Capital Corporation	Texas	Investments		100	%
Premier Tierra Holdings, Inc.	Texas	Liquidating Subsidiary		100	%

Subsidiaries of IBC Subsidiary Corporation

Name	State of Incorporation or Organization	Business	% of Ownership
International Bank of Commerce	Texas	State Bank		100	%
Commerce Bank	Texas	State Bank		100	%
International Bank of Commerce, Zapata	Texas	State Bank		100	%
International Bank of Commerce, Brownsville	Texas	State Bank		100	%
Gulfstar Merchant Banking I, Ltd.	Texas	Investment and Merchant Banking		70	%
Gulfstar Merchant Banking II, Ltd.	Texas	Merchant Banking		70	%
Gulfstar Merchant Banking III, Ltd.	Texas	Merchant Banking		50	%
Gulfstar Merchant Banking IV, Ltd.	Texas	Merchant Banking		50	%

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Exhibit 21

List of Subsidiaries
Subsidiaries of International Bancshares Corporation
Subsidiaries of IBC Subsidiary Corporation