Burlington is a city in, and county seat of, Chittenden County, Vermont, United States. It is located 45 miles (72 km) south of the Canada–United States border and 95 miles (153 km) south of Montreal. As of the 2020 United States census, the population was 44,743. Burlington is the most populous city in Vermont, and is, by population, the smallest U.S. city to be the largest city within a state.