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 KNVLTNMAYAY  829J PAETEC ITEL, LLC 474      
423-520 2 Madisonville TN KNVLTNWHX6X  7476 POWERTEL NASHVILLE LICENSES, INC. 474   2024-03-24   
423-520 4 Madisonville TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2018-04-02   
423-520 6 Madisonville TN KNVLTNMA56Z  124F BANDWIDTH.COM CLEC, LLC - TN 474   2008-11-28   
423-520 7 Madisonville TN KNVLTNMA56Z  124F BANDWIDTH.COM CLEC, LLC - TN 474   2017-06-03   
423-520 8 Madisonville TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2022-12-31   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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