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: 978

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-978 A Chattanooga TN   700J WAVENATION, LLC 472   2025-09-06   
423-978 0 Chattanooga TN   700J WAVENATION, LLC 472   2025-09-06   
423-978 1 Chattanooga TN   124F BANDWIDTH.COM CLEC, LLC - TN 472   2026-06-07   
423-978 8 Chattanooga TN   124F BANDWIDTH.COM CLEC, LLC - TN 472   2026-05-02   
423-978 9 Chattanooga TN   124F BANDWIDTH.COM CLEC, LLC - TN 472   2026-05-02   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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