First Financial Corporation filed a Form S-4 registration statement and preliminary proxy statement/prospectus with the SEC on October 30, 2026, in connection with its proposed merger with First Illinois Corporation under an agreement signed August 26, 2026.

Key Highlights

  • Merger agreement date: First Financial Corporation ("FFC") and First Illinois Corporation entered into an agreement and plan of merger on August 26, 2026.
  • Combined entity size: The filing states the transaction will create a combined bank holding company with approximately $7.0 billion in total assets and a network of 90 branches across Indiana, Illinois, Kentucky, Tennessee, and Georgia.
  • Merger consideration: Each First Illinois share (excluding excluded shares) may be converted into 0.5727 shares of FFC common stock, $44.35 in cash, or a combination of both, subject to proration and allocation procedures.
  • Cash election cap: The maximum number of First Illinois shares convertible into cash consideration is 727,377; the maximum convertible into stock consideration is 1,697,213, subject to proportionate increases if shares are issued upon exercise of First Illinois stock options.
  • Equity adjustment threshold: If First Illinois' adjusted consolidated shareholders' equity as of the closing date is less than $82,437,826, the merger consideration will be adjusted downward on a dollar-for-dollar basis by the amount of the shortfall.
  • Post-merger trading: According to the filing, the combined company will continue to trade on the Nasdaq Stock Market LLC under the ticker symbol "THFF" and will operate under the name "First Financial Corporation."
  • Registrant status: First Financial Corporation is identified in the filing as an accelerated filer and not a smaller reporting company or emerging growth company.

Structure of the Proposed FFC and First Illinois Combination

According to the filing, the transaction involves a series of sequential mergers. Immediately prior to the effective time, HPB Holdings, Inc., a Delaware corporation and wholly owned subsidiary of First Illinois, will merge with and into First Illinois, with First Illinois surviving and thereby becoming the direct owner of Hickory Point Bank and Trust, an Illinois chartered commercial bank. First Illinois will then merge with and into FFC, with FFC as the surviving company. Immediately after that merger, Hickory Point Bank will merge with and into First Financial Bank, National Association, the wholly owned bank subsidiary of FFC, with First Financial Bank as the surviving bank.

The filing describes three election options available to First Illinois shareholders: the stock consideration of 0.5727 shares of FFC common stock per share, the cash consideration of $44.35 per share, or a combination election covering both. The filing notes that because of proration, "a First Illinois shareholder may receive a mix of cash and FFC common stock that differs from the shareholder's election." Shares for which no valid election is made will be treated as stock election shares. Excluded shares, consisting of shares held by First Illinois or FFC outside of fiduciary or agency capacity, will be canceled for no consideration, and shares held by shareholders who properly exercise dissenters' rights under Illinois law are also excluded.

The filing further states that FFC will not issue fractional shares of FFC common stock as part of the stock consideration. The merger agreement also permits FFC to increase, but not decrease, the maximum number of First Illinois shares to be converted into stock consideration, but only in its sole discretion and only if cash elections fall below the maximum cash election threshold. Norman D. Lowery is identified as President and Chief Executive Officer of First Financial Corporation, located at One First Financial Plaza, Terre Haute, Indiana 47807.

What Was Disclosed

First Financial Corporation filed an S-4 registration statement on October 30, 2026, registering common stock to be issued in connection with its proposed merger with First Illinois Corporation. The filing includes a preliminary proxy statement/prospectus addressed to First Illinois shareholders, whose vote the filing describes as "very important."