NPA-NXX - 423-579

This is the 423-579 subcode (NPA-NXX) prefix page. Follow a prefix to find the number you are looking for. We divide our pages up to make them more user friendly to navigate!

1. Area Codes
2. 423
3. 423-579

The 423-579 subcode mainly covers Kingsport in Sullivan county. But other numbers maybe included as well.

We have a database of information derived from the public phone records of Tennessee state. Many of the numbers in this subcode are Regular Landline registered to Mountainet Telephone Company. We hear they employ a large number of people in the Tennessee office.
Recently there have been an increase in reported calls, we've had over 156823 comments across our systems for the 423-579 subcode.