INTERNATIONAL BANCSHARES CORP

Opinion on the Financial Statements

We have audited the accompanying consolidated statements of condition of International Bancshares Corporation and its Subsidiaries (the Company) as of December 31, 2025 and 2024, the related consolidated statements of income, comprehensive income, shareholders' equity and cash flows for each of the three years in the period ended December 31, 2025, and the related notes to the consolidated financial statements (collectively, the financial statements). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2025, based on criteria established inInternal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission in 2013, and our report dated February 26, 2026 expressed an unqualified opinion on the effectiveness of the Company's internal control over financial reporting.