International Bancshares Corporation Announces Increase in Cash Dividend

International Bancshares Corporation (“IBC”) (NASDAQ:IBOC), today announced that on March 19, 2015, its Board of Directors approved the declaration of a 29 cents per share cash dividend for shareholders of record as of the close of business on April 1, 2015, payable on April 17, 2015. “This cash dividend, which reflects an increase of 7.4% per share over IBC’s most recent cash dividend, was made possible because of the continuing favorable performance of IBC during these challenging times from an economic as well as regulatory perspective,” said Dennis E. Nixon, President and CEO of IBC.

It is the inclination of the Board to continue to declare semiannual cash dividends. However, any declaration of future cash dividends will depend upon IBC’s financial position, strategic plans, and general business conditions at the time.

IBC is a multi-bank financial holding company headquartered in Laredo, Texas, with $12.2 billion in total assets, 211 facilities and over 324 ATMs serving 90 communities in Texas and Oklahoma.

“Safe Harbor” statement under the Private Securities Litigation Reform Act of 1995: The statements contained in this release which are not historical facts contain forward-looking information with respect to plans, projections or future performance of IBC and its subsidiaries, the occurrence of which involve certain risks and uncertainties detailed in IBC’s filings with the Securities and Exchange Commission.

Copies of IBC’s SEC filings and Annual Report (as an exhibit to the 10-K) may be downloaded from the SEC filings site located at http://www.sec.gov/edgar.shtml or IBC’s website at http://www.ibc.com.

International Bancshares Corporation, LaredoJudy Wawroski, 956-722-7611First Vice President