IBOC

INTERNATIONAL BANCSHARES CORPORATION_February 26, 2026 0000315709false00003157092026-02-262026-02-26 ​

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): February 26, 2026 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On February 26, 2026, International Bancshares Corporation issued a news release announcing net income for the twelve months ended December 31, 2025.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits ​ ​

EXHIBIT INDEX

Exhibit Number ​ ​ ​ Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated February 26, 2026

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

2

​

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: February 26, 2026 ​ ​

3

INTERNATIONAL BANCSHARES CORPORATION_November 6, 2025 0000315709false00003157092025-11-062025-11-06 ​

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): November 6, 2025 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On November 6, 2025, International Bancshares Corporation issued a news release announcing net income for the three and nine months ended September 30, 2025.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits ​ ​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated November 6, 2025

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

2

​

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: November 6, 2025 ​ ​

3

0000315709false00003157092025-08-072025-08-07 ​

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): August 7, 2025 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On August 7, 2025, International Bancshares Corporation issued a news release announcing net income for the three and six months ended June 30, 2025.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits ​ ​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated August 7, 2025

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

2

​

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: August 7, 2025 ​ ​

3

0000315709false00003157092025-05-052025-05-05 ​

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 5, 2025 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On May 5, 2025, International Bancshares Corporation issued a news release announcing net income for the three months ended March 31, 2025.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated May 5, 2025

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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 5, 2025 ​ ​

4

0000315709false00003157092025-02-272025-02-27 ​

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): February 27, 2025 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On February 27, 2025, International Bancshares Corporation issued a news release announcing net income for the three and twelve months ended December 31, 2024.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated February 27, 2025

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: February 27, 2025 ​ ​

4

0000315709false00003157092024-11-072024-11-07 ​

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): November 7, 2024 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On November 7, 2024, International Bancshares Corporation issued a news release announcing net income for the three and nine months ended September 30, 2024.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated November 7, 2024

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: November 7, 2024 ​ ​

4

0000315709false00003157092024-08-012024-08-01 ​

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): August 1, 2024 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On August 1, 2024, International Bancshares Corporation issued a news release announcing net income for the three and six months ended June 30, 2024.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated August 1, 2024

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: August 1, 2024 ​ ​

4

0000315709false00003157092024-05-022024-05-02 ​

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 2, 2024 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On May 2, 2024, International Bancshares Corporation issued a news release announcing net income for the three months ended March 31, 2024.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated May 2, 2024

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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 2, 2024 ​ ​

4

0000315709false00003157092024-02-262024-02-26 ​

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): February 26, 2024 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

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 ​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On February 26, 2024, International Bancshares Corporation issued a news release announcing net income for the twelve months ended December 31, 2023.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated February 26, 2024

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: February 26, 2024 ​ ​

4

0000315709false00003157092023-11-022023-11-02 ​

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): November 2, 2023 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On November 2, 2023, International Bancshares Corporation issued a news release announcing net income for the three and nine months ended September 30, 2023.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated November 2, 2023

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: November 2, 2023 ​ ​

4

0000315709false00003157092023-08-032023-08-03 ​

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): August 3, 2023 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On August 3, 2023, International Bancshares Corporation issued a news release announcing net income for the three and six months ended June 30, 2023.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated August 3, 2023

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: August 3, 2023 ​ ​

4

0000315709false00003157092023-05-042023-05-04 ​

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 4, 2023 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On May 4, 2023, International Bancshares Corporation issued a news release announcing net income for the three months ended March 31, 2023.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated May 4, 2023

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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 4, 2023 ​ ​

4

0000315709false00003157092023-02-232023-02-23 ​

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): February 23, 2023 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On February 23, 2023, International Bancshares Corporation issued a news release announcing net income for the three and twelve months ended December 31, 2022.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated February 23, 2023

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: February 23, 2023 ​ ​

4

0000315709false00003157092022-08-042022-08-04 ​

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): November 3, 2022 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On November 3, 2022, International Bancshares Corporation issued a news release announcing net income for the three and nine months ended September 30, 2022.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated November 3, 2022

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: November 3, 2022 ​ ​

4

0000315709false00003157092022-08-042022-08-04 ​

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): August 4, 2022 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On August 4, 2022, International Bancshares Corporation issued a news release announcing net income for the three and six months ended June 30, 2022.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated August 4, 2022

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: August 4, 2022 ​ ​

4

0000315709false00003157092022-05-052022-05-05 ​

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 5, 2022 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On May 5, 2022, International Bancshares Corporation issued a news release announcing net income for the three months ended March 31, 2022.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated May 5, 2022

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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 5, 2022 ​ ​

4

0000315709false00003157092022-02-242022-02-24 ​

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): February 24, 2022 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On February 24, 2022, International Bancshares Corporation issued a news release announcing net income for the twelve months ended December 31, 2021.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated February 24, 2022

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: February 24, 2022 ​ ​

4

0000315709false00003157092021-11-042021-11-04 ​

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): November 4, 2021 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On November 4, 2021, International Bancshares Corporation issued a news release announcing net income for the three and nine months ended September 30, 2021.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated November 4, 2021

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: November 4, 2021 ​ ​

4

0000315709false00003157092021-08-052021-08-05 ​

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): August 5, 2021 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On August 5, 2021, International Bancshares Corporation issued a news release announcing net income for the three and six months ended June 30, 2021.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated August 5, 2021

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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: August 5, 2021 ​ ​

4

0000315709false00003157092021-05-062021-05-06 ​

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 6, 2021 ​ ​

INTERNATIONAL BANCSHARES CORPORATION

(Exact name of registrant as specified in its charter) ​ -

​

​

​

​

Texas ​ 000-9439 ​ 74-2157138

(State or other jurisdiction ​ (Commission File ​ (IRS Employer

of incorporation) ​ Number) ​ 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 240.13e-4 (c)) ​ 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. ☐ ​ ​

​

​

​

​

​

Title of Each Class: ​ Trading Symbol (s): ​ Name of each exchange on which registered: ​

Common Stock, $1.00 par value ​

IBOC

​

NASDAQ

​

​ ​ ​

​ ​

Item 2.02          Results of Operations and Financial Condition. On May 6, 2021, International Bancshares Corporation issued a news release announcing net income for the three months ended March 31, 2021.  The news release, attached hereto and filed herewith as Exhibit 99, is incorporated by reference. All of the information furnished in Item 2.02 of this report, including the accompanying exhibits, is also intended to be included under “Item 7.01 – Regulation Fair Disclosure” and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01          Financial Statements and Exhibits (d) Exhibits 99 - The following exhibit is being furnished with this Current Report on Form 8-K. ​

2

​

EXHIBIT INDEX

Exhibit Number

Description

​ ​ ​

99 ​ News Release of International Bancshares Corporation dated May 6, 2021

104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​

3

​

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 6, 2021 ​ ​

4