Spencer is a town located in Worcester County, Massachusetts. It was first settled in 1721 and was officially incorporated in 1775.
According to the United States Census Bureau, the town has a total area of 88.2 km² (34.0 mi²). 85.1 km² (32.8 mi²) of it is land and 3.1 km² (1.2 mi²) of it is water. The total area is 3.52% water.