Buy a Local Phone Number – Area Code 423 (Chattanooga, Tennessee)

Established in 1995 after a division of Tennessee’s longtime 615 territory, 423 came to cover much of the state’s eastern tier, including Chattanooga and the Tri-Cities. In 1999, the Knoxville area was reassigned to 865—a change that created two noncontiguous pockets for this code, one in the southeast around the Tennessee River and another in the northeast along the Appalachian foothills. As with most U.S. numbering plan areas, mandatory 10-digit dialing arrived in 2021.

Chattanooga’s story within the code reflects a shift from rail-and-foundry industry to modern logistics and manufacturing, aided by interstates, a deep rail heritage, and the river port. The northeastern section balances long-standing chemical production in Kingsport with healthcare and higher education centered in Johnson City. Regional culture blends Tennessee Valley influences with Appalachian traditions; Bristol’s 1927 recording sessions and the speedway continue to draw national attention, while cross-border ties to north Georgia shape the metro economy.

• Freight logistics and river/rail transport through the Tennessee Valley
• Automotive assembly and suppliers in the Chattanooga area
• Chemicals and materials centered around Kingsport’s Eastman operations
• Healthcare networks and higher education anchored by Johnson City and regional hubs
• Tourism tied to Appalachian music heritage and motorsports in Bristol