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: 677

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-677 A Fall Branch TN JHCYTNXCX2Y  8645 SUNCOM DBA T-MOBILE USA 956      
423-677 0 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 1 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 2 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 3 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 4 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956   2009-10-23   
423-677 5 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 6 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 7 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 8 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      
423-677 9 Fall Branch TN   8645 SUNCOM DBA T-MOBILE USA 956      

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

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