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: 851

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-851 A New Tazewell TN NWTZTNXADS1  0557 BRIGHTSPEED OF EASTERN TENNESSEE, LLC 474      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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