Greenacres is a locale and former census-designated place (CDP) in Spokane County, Washington, United States. Much of the CDP became part of the city of Spokane Valley upon its incorporation in 2003. An additional 644 acres (2.61 km2) became part of the city of Liberty Lake in 2006. The population was 5,158 at the 2000 census. Greenacres also has two schools in the Central Valley School District named after it; Greenacres Middle School and Greenacres Elementary School.