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: 943

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-943 A Johnson City TN JHCYTNXCX2Y  8645 SUNCOM DBA T-MOBILE USA 956      
423-943 0 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 1 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 2 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 3 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 4 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 5 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 6 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 7 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 8 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-943 9 Johnson City TN   8645 SUNCOM DBA T-MOBILE USA 956      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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