Kalispell is a city in Flathead County, Montana, USA. The population was 14,223 at the 2000 census. A 2004 estimate placed its population at 17,381. It is the county seat of Flathead County. Kalispell is the largest city and commercial center of Northwest Montana. The name Kalispell is a Salish word meaning 'flat land above the lake.' Kalispell apartments for rent comparison page shows most up to date rent information on Kalispell apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.