Polson (Salish: nč̓mqnetkʷ, Ktunaxa: kwat̕aq̓nuk) is a city in Lake County, Montana, United States, on the southern shore of Flathead Lake. It is also on the Flathead Indian Reservation. The population was 4,488 at the 2010 census. It is the county seat of Lake County. The city was named after pioneer rancher David Polson.