Fosston is a city in Polk County, Minnesota, United States. It is part of the 'Grand Forks-ND-MN Metropolitan Statistical Area'. The population was 1,527 at the 2010 census.
According to the United States Census Bureau, the city has a total area of 1.6 square miles (4.2 km²), of which, 1.6 square miles (4.2 km²) of it is land and 0.04 square miles (0.1 km²) of it (1.22%) is water.
Four-lane U.S. Highway 2 serves as a main route in the city.