Belchertown is a town in Hampshire County, Massachusetts, United States. It is part of the Springfield, Massachusetts Metropolitan Statistical Area. The population was 15,350 at the 2020 census. The town includes the census-designated place of Belchertown. Belchertown was formerly the home of the Belchertown State School. The land on which the school sat is, as of 2016, being redeveloped for mixed uses including residential, commercial and recreational.