Brattleboro (/ˈbrætəlbʌroʊ/), originally Brattleborough, is a town in Windham County, Vermont, United States. The most populous municipality abutting Vermont's eastern border with New Hampshire, which is the Connecticut River, Brattleboro is located about 10 miles (16 km) north of the Massachusetts state line, at the confluence of Vermont's West River and the Connecticut. As of the 2020 Census, the population was 12,184.