Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For The Quarterly Period Ended March 31, 2024 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) Indiana 35-1546989 (State or other ju ...

Exhibit 99.1 News Release FIRST FINANCIAL CORPORATION One First Financial Plaza, Terre Haute, Indiana 47807 (812) 238-6000 First Financial Corporation Reports First Quarter Results Terre Haute, Indiana, April 30, 2024 – First Financial Corporation (NASDAQ:THFF) today announced results for the first quarter of 2024. ● Net income was $10.9 million compared to the $16.0 million reported for the same period of 2023; ● Diluted net income per common share of $0.93 compared to $1.33 for the same period of 2023; ● ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) Indiana 35-1546989 (State of Incorporat ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For The Quarterly Period Ended September 30, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) (812) 238-6000 (Registrant's tele ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For The Quarterly Period Ended June 30, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) Indiana 35-1546989 (State or other jur ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For The Quarterly Period Ended March 31, 2023 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) Indiana 35-1546989 (State or other ju ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 0-16759 FIRST FINANCIAL CORPORATION (Exact name of registrant as specified in its charter) Indiana 35-1546989 (State of Incorporat ...