Old Second Bancorp, Inc. operates as the bank holding company for Old Second National Bank that provides community banking services in the United States. The company offers deposit products, including consumer and business checking, NOW, money market, savings, and other time deposit accounts, as well as certificates of deposit and individual retirement accounts. It also offers lending products, such as commercial and industrial loans; commercial real estate loans; multifamily loans; construction and development loans; residential real estate loans, such as residential first mortgage and second mortgage loans; home equity lines of credit; consumer loans, including motor vehicle, home improvement, and signature loans; installment and agricultural loans; lease financing receivables and overdraft checking; and safe deposit operations. In addition, the company provides online and mobile banking; corporate cash management products, including remote and mobile deposits capture, investment sweep accounts, zero balance accounts, automated tax payments, automatic teller machines access, telephone banking, lockbox accounts, automated clearing house transactions, account reconciliation, controlled disbursement, detail and general information reporting, foreign and domestic wire transfers, and vault services for currency and coin; and investment, agency, and custodial services for individual, corporate, and not-for-profit clients. The company was founded in 1871 and is headquartered in Aurora, Illinois.