Post Falls is a city in Kootenai County, Idaho, between Coeur d'Alene and Spokane, Washington. It is a suburb of Coeur d'Alene, to the east, and a bedroom community to Spokane, to the west. The population was 27,574 at the 2010 census, up from 17,247 in 2000 census, making it Idaho's tenth largest city. The U.S. Census Bureau estimated 2019 population is 36,250.