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: 731

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-731 A New Tazewell TN   792K CHARTER IP ENABLED SERVICES, LLC 474   2026-01-25   
423-731 1 New Tazewell TN   792K CHARTER IP ENABLED SERVICES, LLC 474   2026-01-25   

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

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