Dexter is a town in Penobscot County, Maine, United States. The population was 3,895 at the 2010 census. It is part of the Bangor metropolitan statistical area. Dexter Regional High School, which serves Dexter as well as other nearby small towns, is located in the town.
Dexter was settled beginning in 1801 by Ebenezer Small, David Smith, and others from New Hampshire, and was originally called Elkinstown. When incorporated as a town in 1816, it named itself after Judge Samuel Dexter, who was then running for governor of Massachusetts (of which Maine was still a part). The town of Brooks in nearby Waldo County was incorporated the same year and named for the opposing candidate, John Brooks. Brooks won the election. The town of Dexter, however, achieved the greater prosperity.
The town grew because of its location on the East Branch of the Sebasticook River, which provided excellent water power for mills. In 1818, Jonathan Farrar constructed a grist mill at the falls.