Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 578

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-578 A Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 0 Kingsport TN JHCYTNXCXYX  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 956   2007-08-31   
423-578 1 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 2 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 3 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 4 Kingsport TN JHCYTNXCXIY  6673 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN 956   2009-02-05   
423-578 5 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 6 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 7 Kingsport TN GTCYVA02AMD  008A MOUNTAINET TELEPHONE COMPANY - TN 956   2003-08-25   
423-578 8 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      
423-578 9 Kingsport TN KGPTTNXADS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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