Colchester is a town in Chittenden County, Vermont, United States. The population was 17,067 as of the 2010 census. It is the fourth-most populous municipality and second-most populous town in the state of Vermont. Colchester is a suburb of Burlington–Vermont's most populous municipality. The town is directly to Burlington's north on the eastern shore of Lake Champlain, to the west of the Green Mountains. The Vermont National Guard is based in the town, and it is also home to Saint Michael's College and the Vermont campuses of the Albany College of Pharmacy and Health Sciences and Southern New Hampshire University.
Colchester is located on the shore of Malletts Bay, part of Lake Champlain. The westernmost part of the town touches the New York state border in the middle of the lake. To the northwest, across the eastern arm of the lake, lies the town of South Hero in Grand Isle County. Chittenden County communities bordering Colchester are Milton to the northeast, Westford touching the easternmost point of Colchester, Essex to the southeast, and the cities of South Burlington, Winooski, and Burlington to the south.