Area Coe 865 is an area code in the U.S. state of Tennessee. It consists of Knox County and the other eight central East Tennessee counties that border it (Anderson, Blount, Grainger, Jefferson, Loudon, Roane, Sevier, and Union). The area code region incorporates most of the region defined as the Knoxville-Sevierville-La Follette Combined Statistical Area. Cities in the 865 area code include Knoxville, Gatlinburg, Harriman, Jefferson City, Lenoir City, Maryville, Maynardville, Oak Ridge, Rockwood, Rutledge, and Sevierville.