CNB Bank Shares, Inc. operates as the bank holding company for CNB Bank & Trust. N.A. that provides banking services to individual and corporate customers in south-central Illinois, suburban southwestern Chicago, and the St. Louis metropolitan area. The company offers checking and savings accounts, certificates of deposits, time deposits, and individual retirement accounts; loans and credits, which include mortgage, construction, home equity, customer installment, student, commercial real estate, government guaranteed, term business, working capital, small business, commercial, and agricultural loans, as well as lines of credit and letters of credits; equipment financing; loans to acquire existing business; and leasing services. It provides overdraft, night depository, safe deposit box, cash management, wire transfer, cashier's check, and notary services; gift cards, and credit and debit cards; digital wallet; mobile check deposit; online and mobile banking services; wealth management, and farm management and agricultural consulting services. The company was founded in 1854 and is headquartered in Carlinville, Illinois.