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: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-600 A Apison TN CHTGTNNSXRZ  318J COMCAST IP PHONE, LLC 472      
423-600 0 Apison TN   318J COMCAST IP PHONE, LLC 472   2007-05-03   
423-600 1 Apison TN   525E ONVOY, LLC - TN 472   2021-03-15   
423-600 2 Apison TN   525E ONVOY, LLC - TN 472   2021-05-22   
423-600 4 Apison TN   525E ONVOY, LLC - TN 472   2021-10-23   
423-600 5 Apison TN   525E ONVOY, LLC - TN 472   2023-02-10   
423-600 6 Apison TN   525E ONVOY, LLC - TN 472   2019-08-26   
423-600 7 Apison TN   145J TERRA NOVA TELECOM INC. 472   2025-11-22   
423-600 8 Apison TN   525E ONVOY, LLC - TN 472   2023-09-18   
423-600 9 Apison TN   124F BANDWIDTH.COM CLEC, LLC - TN 472   2008-11-28   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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