Stow is a town in Middlesex County, Massachusetts, United States. The town is located 21 miles west of Boston, in the MetroWest region of Massachusetts. The population was 7,174 at the 2020 census. Stow was officially incorporated in 1683 with an area of approximately 40 square miles. Over centuries it gave up land as newer, smaller towns were created, ceding land to Harvard, Shirley, Boxborough, Hudson and Maynard. Stow now has an area of 18.1 square miles.