Colchester is a town in New London County, Connecticut, United States. The population was 14,551 at the 2000 census. In 2005 it was ranked 57th on the "100 Best Places to Live" in all of the United States, conducted by CNN. In 2010 Colchester became the first town in Connecticut, and the 36th in the country, to be certified with the National Wildlife Federation (NWF) as a Community Wildlife Habitat. Colchester is one of the fastest growing towns in Connecticut. The villages of Westchester and North Westchester are located within Colchester, as is the reservation of the Golden Hill Paugussett Indian Nation. The town center village, which was previously incorporated as a borough, is a census-designated place.
The Colchester Historical Society operates a local history museum in town.
According to the United States Census Bureau, the town has a total area of 49.8 square miles (129.0 km²), of which, 49.1 square miles (127.1 km²) of it is land and 0.7 square miles (1.9 km²) of it (1.49%) is water.