Area code 423

Area code 423 is a telephone area code in the North American Numbering Plan for the U.S. state of Tennessee. It comprises two disconnected areas of East Tennessee that are separated by area code 865.

Principal cities in the northern part of the area code region are Morristown, Greeneville, Kingsport, Johnson City, and Bristol (more commonly known as the Tri-Cities region). The principal cities in the south are Chattanooga and Cleveland.