Form 8-K

8-K — INTERNATIONAL BANCSHARES CORP

Accession: 0001104659-26-113899

Filed: 2026-10-06

Period: 2026-10-06

CIK: 0000315709

SIC: 6022 (STATE COMMERCIAL BANKS)

Item: Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — tm2627039d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2627039d1_ex99-1.htm)

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8-K — FORM 8-K

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0000315709

2026-10-06

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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):

October 6, 2026

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter)

Texas

000-09439

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 3.01 Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

On October 6, 2026, International Bancshares Corporation

(the “Company”), acting pursuant to authorization from its Board of Directors, notified The Nasdaq Stock Market LLC (“Nasdaq”)

of its intention to voluntarily withdraw the listing of the Company’s common stock, par value $1.00 per share (the “Common

Stock”), from Nasdaq and transfer the listing to the Texas Stock Exchange LLC (“TXSE”). The Company expects the listing

and trading of its Common Stock on Nasdaq to cease at the close of trading on Friday, October 16, 2026, and the listing and trading of

its Common Stock on TXSE to begin at market open on Monday, October 19, 2026. The Common Stock has been approved for listing on TXSE,

where it will continue to trade under the ticker symbol “IBOC.”

Item 7.01 Regulation FD Disclosure.

On October 6, 2026, the Company issued a press

release announcing the anticipated transfer of the listing of its Common Stock to TXSE. A copy of the press release is furnished as Exhibit

99.1 to this Current Report on Form 8-K and is incorporated herein by reference. The information furnished under this Item 7.01,

including the referenced exhibit, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act

of 1934, as amended (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing under the Securities

Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description

99.1

Press Release of International Bancshares Corporation dated October 6, 2026

104

Cover page Interactive Data File (embedded within the Inline XBRL document)

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: October 6, 2026

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2627039d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

International

Bancshares Corporation

to Transfer Primary Listing to Texas Stock Exchange

Ticker symbol

to remain “IBOC”

LAREDO, Texas—(BUSINESS

WIRE)—October 6, 2026—International Bancshares Corporation (NASDAQ: IBOC) (“IBC”), one of the largest independent

bank holding companies in Texas, today announced its plans to transfer the primary listing of its common stock from the Nasdaq Stock

Market (“Nasdaq”) to the Texas Stock Exchange (“TXSE”). IBC expects its common stock to begin trading on TXSE

at market open on Monday, October 19, 2026, under its current ticker symbol “IBOC.”

“Texas has

long been a place where free enterprise principles have allowed businesses to build, grow, and lead, and we are excited to continue that

legacy by bringing IBC’s primary listing to the state where our business has prospered for 60 years,” said Dennis E.

Nixon, IBC’s Chairman and CEO. “We are proud to join the Texas Stock Exchange and are confident in its ability to create

new opportunities for our business and our investors.”

IBC’s decision

to transfer the primary listing of its common stock to TXSE is grounded in its longstanding ties to Texas, where its operations, customer

base, and community relationships are centered. Headquartered in Laredo, where its flagship bank was founded in 1966, IBC serves 75 communities

across Texas and Oklahoma through its five subsidiary banks. IBC is proud to be at the forefront of this new chapter in Texas’s

capital markets and believes TXSE will be a catalyst for capital formation, business growth, and market innovation. IBC’s move

to TXSE aligns its deep roots in the Lone Star State with its long-term focus on delivering lasting value to shareholders.

“IBC is one

of the great franchises in Texas banking — opened in Laredo in 1966 with less than $1 million in assets and grown into a $17 billion

institution trusted by generations of businesses and families,” said James H. Lee, chairman and CEO of TXSE. “The Texas Stock

Exchange was built to power American success stories like IBC, and we are proud to have earned its primary listing.”

No action is required

by IBC’s shareholders in connection with the transfer of IBC’s listing to TXSE. IBC’s common stock will continue trading

on Nasdaq until the close of market on Friday, October 16, 2026.

Closing-Bell

Ceremony

IBC looks forward

to celebrating its historic move to TXSE at a closing-bell ceremony that it plans to hold in Houston, Texas, on December 7, 2026.

About International

Bancshares Corporation

IBC is a registered

multibank financial holding company headquartered in Laredo, Texas. IBC provides a diversified range of commercial and retail banking

services through 165 facilities and 245 ATMs across north, south, central, and southeast Texas and the State of Oklahoma. IBC owns five

separately chartered banks ranging in size from approximately $567 million to $10.2 billion in assets, with IBC’s consolidated

assets totaling approximately $17.0 billion. For more information on IBC, please visit https://www.ibc.com.

Forward-Looking

Statements

This communication

contains “forward-looking statements” within the meaning of and pursuant to the Private Securities Litigation Reform Act

of 1995 regarding, among other things, IBC’s planned transfer of its primary listing to TXSE and the expected benefits from and

impact of that transfer. Although management believes such forward-looking statements are based on reasonable assumptions, no assurance

can be given that every objective will be reached. The words “estimate,” “expect,” “intend,” “believe,”

and “project,” as well as other words or expressions of a similar meaning, are intended to identify forward-looking statements.

Because forward-looking

statements relate to future results and occurrences, they are subject to inherent and various uncertainties, risks, and changes in circumstances

that are difficult to predict. These statements may change over time, are based on management’s expectations and assumptions at

the time the statements are made, and should be viewed with caution. Actual results and experience may differ materially from the forward-looking

statements as a result of numerous risks and other factors, many of which are beyond management’s control. While there can be no

assurance that any list of risks is complete, important risks and other factors that could cause actual results to differ materially

from those contemplated by forward-looking statements include but are not limited to operational, regulatory, or technical challenges

related to the TXSE listing, as well as the risks and factors more fully described in IBC’s most recent Annual Report on Form 10-K,

Quarterly Reports on Form 10-Q, and other documents and filings with the Securities and Exchange Commission. The information contained

in this communication speaks only as of its date. Except to the extent required by applicable law or regulation, IBC disclaims any obligation

to update any forward-looking statements or to publicly announce the results of any revisions to any of the forward-looking statements

included herein to reflect future events or developments.

Contact Information

Investor Relations

Eliza V. Gonzalez

(956) 722-7611

ElizaGonzalez@ibc.com

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