Area Code 423 History:
Area code 423 was put into service. Area code 423 was created from a split of area code 615. In 1999 area code 423 was split to form area code 865.
Counties in Tennessee within area code 423 include:
Bledsoe County, Bradley County, Campbell County, Carter County, Claiborne County, Cocke County, Greene County, Hamblen County, Hamilton County, Hancock County, Hawkins County, Johnson County, Marion County, McMinn County, Meigs County, Monroe County, Morgan County, Polk County, Rhea County, Roane County, Scott County, Sequatchie County, Sullivan County, Unicoi County, and Washington County.
Major cities or places in Tennessee within area code 423 include:
Area code 423 serves two distinct geographic areas in Tennessee that are not contiguous, including the larger cities and communities of Bristol, Johnson City and Kingsport in northeastern Tennessee and Chattanooga and Cleveland in the southern areas in addition to many smaller communities.