423 Area Code is part of 23 counties in the state of Tennessee. There are around 37 cities and 73 other places such as towns, cdps and villages in the 423 area code. Area code 423 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of Tennessee. Below you will find more info about Code and also zip codes, counties, cities and the post offices that belong to this Area Code.
Sources: North American Numbering Plan Administration (NANPA), telecom providers, and the U.S. Census Bureau.