Form 8-K

8-K — INTERNATIONAL BANCSHARES CORP

Accession: 0001104659-26-064211

Filed: 2026-05-20

Period: 2026-05-18

CIK: 0000315709

SIC: 6022 (STATE COMMERCIAL BANKS)

Item: Submission of Matters to a Vote of Security Holders

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

May 18, 2026

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in

its charter)

Texas

000-9439

74-2157138

(State or other

jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

1200 San Bernardo, Laredo, Texas

78040-1359

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including

area code: (956) 722-7611

None

(Former name or former address, if changed

since last report.)

Check the appropriate box below if the Form 8-K filing

is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General

Instruction A.2.below):

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 250.13e-4(c))

Securities registered pursuant to Section 12(b) of

the Act:

Title of each class:

Trading Symbol(s)

Name of each exchange on which registered:

Common Stock, $1.00 par value

IBOC

The Nasdaq Stock Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405

of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth

company ¨

If an emerging

growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with

any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 5.07. Submission of Matters

to a Vote of Security Holders.

On May 18, 2026, International

Bancshares Corporation (the “Company”) held its 2026 Annual Meeting of Shareholders (the “Annual Meeting”). As

described in the Company’s definitive proxy statement on Schedule 14A filed with the Securities and Exchange Commission on

April 20, 2026 (the “Proxy Statement”), the Company submitted the following proposals to its shareholders for a vote:

(1) To elect eight (8) directors to serve until the next Annual Meeting of Shareholders and until their

successors are duly elected and qualified;

(2) To ratify the appointment of RSM US LLP as the Company’s independent auditor for the fiscal year

ending December 31, 2026; and

(3) To consider and approve a non-binding advisory resolution to approve the compensation of the Company’s

named executive officers as described in the Compensation Discussion and Analysis and the tabular disclosures in the Proxy Statement.

The following table lists the final

voting results for Proposals 1, 2, and 3 at the Annual Meeting:

For

Against

Abstain

Broker Non-Votes

Election of Directors

Javier de Anda

50,312,229

692,795

12,067

5,172,819

Douglas B. Howland

42,540,965

8,452,097

24,029

5,172,819

Rudolph M. Miles

50,435,028

552,129

29,934

5,172,819

Dennis E. Nixon

49,981,267

1,026,700

9,124

5,172,819

Larry A. Norton

42,598,196

8,394,863

24,032

5,172,819

Roberto R. Reséndez

44,548,418

6,444,642

24,031

5,172,819

Antonio R. Sanchez, Jr.

43,800,283

7,206,098

10,710

5,172,819

Diana G. Zuniga

44,808,267

6,183,294

25,530

5,172,819

Ratification of RSM US LLP

55,979,590

195,629

14,691

Non-binding Advisory Resolution on Compensation

49,397,712

1,592,585

26,794

5,172,819

Based on the foregoing results,

each director nominee named above was elected by a majority-vote standard, which is the voting standard required by the Company’s

Articles of Incorporation for uncontested director elections. Proposals 2 and 3 were also approved by a majority vote.

SIGNATURES

Pursuant to the requirements

of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto

duly authorized.

INTERNATIONAL BANCSHARES CORPORATION

By:

/s/ Dennis E. Nixon

Dennis E. Nixon

President and Chief Executive Officer

Date: May 20, 2026

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