Mercantile Bancorp said it has an agreement to buy First Financial Corporation of America, Salem, Mo., for $15 million in cash and stock.
The deal, which would bring Mercantile into central Missouri, is subject to approval by First Financial shareholders and regulatory authorities.
First Financial's $85 million-asset First National Bank of Salem would be a separate community bank within the consolidated Mercantile Bank of Central Missouri charter.
The exchange ratio is 4.2963 shares of Mercantile common stock, or $194.73 per share, for every share of First Financial.
Mercantile Bancorp, with $18 billion in assets, operates banks in Missouri, Iowa, Kansas, Illinois, and Arkansas.
The bank has two other mergers pending: with $510 million-asset Today's Bancorp in northwestern Illinois and $94 million-asset Peoples State Bank in Topeka, Kan.