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: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-399 A Sullivan Gardens TN   124F BANDWIDTH.COM CLEC, LLC - TN 956   2026-04-09   
423-399 0 Sullivan Gardens TN   124F BANDWIDTH.COM CLEC, LLC - TN 956   2026-04-09   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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