Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 390

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-390 A Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 0 Kingsport TN JHCYTNXCXNX  124F BANDWIDTH.COM CLEC, LLC - TN 956      
423-390 1 Kingsport TN   792K CHARTER IP ENABLED SERVICES, LLC 956      
423-390 2 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 3 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 4 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 5 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 6 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 7 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-390 8 Kingsport TN JHCYTNXCXNX  124F BANDWIDTH.COM CLEC, LLC - TN 956      
423-390 9 Kingsport TN JHCYTNXCXNX  124F BANDWIDTH.COM CLEC, LLC - TN 956      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.