THFF

FIRST FINANCIAL CORPORATION_February 3, 2026 0000714562false00007145622026-02-032026-02-03 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 3, 2026 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On February 3, 2026, the Registrant issued a press release reporting its financial results for the year ended December 31, 2025. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number ​ ​ ​ ​

​ ​ ​

99.1 ​ Press Release, February 3, 2026, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated February 3, 2026 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

FIRST FINANCIAL CORPORATION_October 28, 2025 0000714562false00007145622025-10-282025-10-28 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 28, 2025 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On October 28, 2025, the Registrant issued a press release reporting its financial results for the three and nine months ended September 30, 2025. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, October 28, 2025, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated October 28, 2025 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622025-07-222025-07-22 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) July 22, 2025 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On July 22, 2025, the Registrant issued a press release reporting its financial results for the three and six months ended June 30, 2025. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, July 22, 2025, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated July 22, 2025 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622025-04-222025-04-22 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 22, 2025 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On April 22, 2025, the Registrant issued a press release reporting its financial results for the three months ended March 31, 2025. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, April 22, 2025, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated April 22, 2025 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622025-02-042025-02-04 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 4, 2025 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On February 4, 2025, the Registrant issued a press release reporting its financial results for year ended December 31, 2024. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, February 4, 2025, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated February 4, 2025 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622024-10-222024-10-22 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 22, 2024 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On October 22, 2024, the Registrant issued a press release reporting its financial results for the three and nine months ended September 30, 2024. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, October 22, 2024, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated October 22, 2024 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622024-07-232024-07-23 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) July 23, 2024 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On July 23, 2024, the Registrant issued a press release reporting its financial results for the three and six months ended June 30, 2024. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, July 23, 2024, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated July 23, 2024 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622024-04-302024-04-30 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 30, 2024 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On April 30, 2024, the Registrant issued a press release reporting its financial results for the three months ended March 31, 2024. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, April 30, 2024, issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated April 30, 2024 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622024-01-302024-01-30 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) January 30, 2024 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On January 30, 2024, the Registrant issued a press release reporting its financial results for the year ended December 31, 2023. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, January 30, 2024 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated January 30, 2024 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622023-10-242023-10-24 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 24, 2023 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On October 24, 2023, the Registrant issued a press release reporting its financial results for the three and nine months ended September 30, 2023. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, October 24, 2023 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated October 24, 2023 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622023-07-252023-07-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) July 25, 2023 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On July 25, 2023, the Registrant issued a press release reporting its financial results for the three and six months ended June 30, 2023. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, July 25, 2023 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated July 25, 2023 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622023-04-252023-04-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 25, 2023 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On April 25, 2023, the Registrant issued a press release reporting its financial results for the three months ended March 31, 2023. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, April 25, 2023 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated April 25, 2023 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622023-02-072023-02-07 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 7, 2023 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On February 7, 2023, the Registrant issued a press release reporting its financial results for the year ended December 31, 2022. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, February 7, 2023 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated February 7, 2023 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

0000714562false00007145622022-10-252022-10-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 25, 2022 ​

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter) ​ Commission File Number: 0-16759 ​ Indiana 35-1546989

(State or other jurisdiction (I.R.S. Employer

incorporation or organization) Identification No.)

​ ​ ​

One First Financial Plaza, Terre Haute, IN 47807

(Address of principal executive office) (Zip Code)

​ ​ ​

(812)  238-6000 ​

(Registrant's telephone number, including area code)

​ 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: ​ ☐Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ​ ☐Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) ​ Securities registered pursuant to Section 12(b) of the Act: ​ Title of each class ​ Trading Symbol ​ Name of each exchange on which registered

Common Stock, par value $0.125 per share ​

THFF

​ The NASDAQ Stock Market LLC

​ Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). ​ 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 2.02. Results of Operations and Financial Condition ​ On October 25, 2022, the Registrant issued a press release reporting its financial results for the three and nine months ended September 30, 2022. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety. ​ The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing. ​ Item 9.01. Financial Statements and Exhibits ​ The exhibit to this report is as follows: ​ Exhibit Number

​

​ ​ ​

99.1 ​ Press Release, October 25, 2022 issued by First Financial Corporation

104 ​ Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)

​ ​ ​

SIGNATURES

​ Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ First Financial Corporation

​ ​

Dated October 25, 2022 ​

​ /s/ Rodger A. McHargue

​ Rodger A. McHargue

​ Secretary/Treasurer and Chief Financial Officer

​ ​ ​

thff-2022072600007145622022Q2FALSEOne First Financial PlazaTerre HauteIN00007145622022-07-262022-07-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) July 26, 2022

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On July 26, 2022, the Registrant issued a press release reporting its financial results for the three and six months ended June 30, 2022. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, July 26, 2022 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  July 26, 2022 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer

thff-2022042600007145622022Q1FALSEOne First Financial PlazaTerre HauteIN00007145622022-04-262022-04-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 26, 2022

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On April 26, 2022, the Registrant issued a press release reporting its financial results for the three months ended March 31, 2022. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, April 26, 2022 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  April 26, 2022 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer

thff-2022020100007145622021FYFALSEOne First Financial PlazaTerre HauteIN00007145622022-02-012022-02-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 1, 2022

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On February 1, 2022, the Registrant issued a press release reporting its financial results for the year ended December 31, 2021. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, February 1, 2022 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  February 1, 2022 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer

thff-2021102600007145622021Q3FALSEOne First Financial PlazaTerre HauteIN00007145622021-10-262021-10-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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 26, 2021

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On October 26, 2021, the Registrant issued a press release reporting its financial results for the three and nine months ended September 30, 2021. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, October 26, 2021 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  October 26, 2021 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer

thff-2021042700007145622021Q2FALSEOne First Financial PlazaTerre HauteIN00007145622021-07-272021-07-27

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 27, 2021

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On July 27, 2021, the Registrant issued a press release reporting its financial results for the three and six months ended June 30, 2021. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, July 27, 2021 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  July 27, 2021 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer

thff-2021042700007145622021Q1FALSEOne First Financial PlazaTerre HauteIN00007145622021-04-272021-04-2700007145622020-10-272020-10-27

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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) April 27, 2021

FIRST FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Commission File Number: 0-16759

Indiana35-1546989 (State or other jurisdiction(I.R.S. Employer incorporation or organization)Identification No.)

One First Financial Plaza, Terre Haute, IN 47807 (Address of principal executive office)(Zip Code)

(812)238-6000 (Registrant's telephone number, including area code)

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:

☐ Written communication 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 communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading SymbolName of each exchange on which registered Common Stock, par value $0.125 per shareTHFFThe NASDAQ Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 2.02. Results of Operations and Financial Condition

On April 27, 2021, the Registrant issued a press release reporting its financial results for the three months ended March 31, 2021. A copy of the press release is being furnished as an exhibit to this report and is incorporated herein by reference in its entirety.

The foregoing information, including the information contained in the press release, is being furnished pursuant to this Item 2.02 and shall not be deemed to be “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. In addition, this information shall not be deemed to be incorporated by reference into any of the Registrant’s filings with the Securities and Exchange Commission, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits

The exhibit to this report is as follows:

Exhibit Number

99.1 Press Release, April 27, 2021 issued by First Financial Corporation

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

First Financial Corporation

Dated  April 27, 2021 /s/Rodger A. McHargue Rodger A. McHargue Secretary/Treasurer and Chief Financial Officer