Nine Mile Falls is an unincorporated community in Spokane County, Washington and Stevens County, Washington, United States. It is located 9 mi downstream on the winding river from downtown Spokane, at the location of the former falls on the Spokane River. In 1908, the falls were eliminated by the construction of Nine Mile Dam.The community offers four schools: two elementary schools, one middle school and a high school. Both Lakeside High and Lakeside Middle are home to the Eagles. Lake Spokane Elementary, home of the Mustangs, and Nine Mile Falls Elementary, home of the Lakers, are elementary schools in the community.Nine Mile Falls has a post office with zip code 99026. The town is also the site of the historic Spokane House trading post, established in 1810. Spokane House was one of the first white settlements in the area. The western trailhead of the Spokane River Centennial Trail is at Sontag Park in Nine Mile Falls.