Area code 865 serves Knoxville, Tennessee, and the nine surrounding counties (Anderson, Blount, Grainger, Jefferson, Knox, Loudon, Roane, Sevier, and Union) in central East Tennessee. The area incorporates most of the region defined as the Knoxville-Sevierville-La Follette Combined Statistical Area.
Cities in the 865 area include Knoxville, Alcoa, Bean Station, Clinton, Gatlinburg, Harriman, Jefferson City, Kingston, Lenoir City, Maryville, Maynardville, Norris, Oak Ridge, Pigeon Forge, Plainview, Rockwood, Rutledge, Sevierville and Townsend.