Grand Isle is a town on Grand Isle in Grand Isle County, Vermont, United States. The population was 2,067 at the 2010 census.
A landing for the Lake Champlain Transportation Company's ferry to Plattsburgh, New York, at Cumberland Head is located on the western shore of Grand Isle at Gordon's Landing.
The town was originally named "Middle Hero" when it was subdivided from the town of "South Hero" in November 1798. In November 1810, the town was renamed "Grand Isle".
The town of Grand Isle occupies the northern half of South Hero Island, also known as "Grand Isle", in Lake Champlain. It is bordered to the south by the town of South Hero and to the north by the town of North Hero, both in Grand Isle County. To the west, across the western channel of Lake Champlain, is the town of Plattsburgh in Clinton County, New York, while to the east, across the eastern channel of Lake Champlain, is the town of Milton in Chittenden County, Vermont, and the town of St. Albans in Franklin County, Vermont. The town of Grand Isle includes Savage Island in the eastern part of town, and the much smaller Young Island and Bixby Island, comprising the Sister Islands, in the northwest part of town. Grand Isle State Park, with frontage on Lake Champlain, is in the southeast part of town.
According to the United States Census Bureau, the town has a total area of 35.1 square miles (91.0 km2), of which 16.4 square miles (42.5 km2) are land and 18.7 square miles (48.5 km2), or 53.27%, are water.
As of the census of 2000, there were 1,955 people, 772 households, and 572 families residing in the town.