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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-423 A Limestone TN   792K CHARTER IP ENABLED SERVICES, LLC 956   2026-01-11   
423-423 1 Limestone TN   792K CHARTER IP ENABLED SERVICES, LLC 956   2026-01-11   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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