Kalispell is a city in Montana and the county seat of Flathead County, Montana, United States. The 2020 census put Kalispell's population at 24,558. In Montana's northwest region, it is the largest city and the commercial center of the Kalispell Micropolitan Statistical Area. The name Kalispell is a Salish word meaning "flat land above the lake".

The Salish or Séliš language, also known as Kalispel–Pend d'oreille, Kalispel–Spokane–Flathead, or Montana Salish to distinguish it from other Salishan languages, is a Salishan language spoken by about 64 elders of the Flathead Nation in north central Montana and of the Kalispel Indian Reservation in northeastern Washington state, and by another 50 elders of the Spokane Indian Reservation of Washington. As of 2012, Salish is "critically endangered" in Montana and Idaho according to UNESCO.