BSB Bancorp, Inc. operates as the holding company for Belmont Savings Bank that provides commercial and retail banking services to small businesses, municipalities, nonprofit organizations, and other customers in the United States. Its deposit products include relationship checking accounts for consumers and businesses, passbook and statement savings accounts, certificates of deposit, money market accounts, interest on lawyer trust accounts, and individual retirement accounts, as well as commercial, municipal, and regular checking accounts. The company’s loan portfolio comprises one to four family residential mortgage loans, commercial real estate loans, multi-family real estate loans, home equity lines of credit, indirect automobile loans, commercial business loans, construction loans and investment securities, other consumer loans, and second mortgage loans. It also offers lockbox, online and mobile banking, global payments, and cash management services. The company operates through six full-service branch offices located in Belmont, Watertown, Waltham, Newton, and Cambridge in Southeast Middlesex County, Massachusetts. The company was founded in 1885 and is headquartered in Belmont, Massachusetts.