Old Second Bancorp, Inc. is the bank holding company for Old Second National Bank, providing community banking services in the United States. It offers deposit products such as checking, NOW, money market, savings, and time deposit accounts, as well as certificates of deposit and individual retirement accounts. Its lending products include commercial and industrial, commercial real estate, multifamily, construction and development, residential real estate, home equity lines of credit, consumer, installment, and agricultural loans, along with lease financing receivables and overdraft checking. The company also provides online and mobile banking, corporate cash management, and investment, agency, and custodial services. Founded in 1871, it is headquartered in Aurora, Illinois.