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: 520

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-520 A Madisonville TN KNVLTNMAYAY  829J PAETEC ITEL, LLC 474   2024-12-05   
423-520 0 Madisonville TN   145J TERRA NOVA TELECOM INC. 474   2023-08-10   
423-520 1 Madisonville TN   829J PAETEC ITEL, LLC 474      
423-520 2 Madisonville TN   7476 POWERTEL NASHVILLE LICENSES, INC. 474   2024-03-24   
423-520 4 Madisonville TN   525E ONVOY, LLC - TN 474   2018-04-02   
423-520 6 Madisonville TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2008-11-28   
423-520 7 Madisonville TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2017-06-03   
423-520 8 Madisonville TN   525E ONVOY, LLC - TN 474   2022-12-31   

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

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