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: 720

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-720 A Newport TN KNVLTNMA56Z  124F BANDWIDTH.COM CLEC, LLC - TN 474      
423-720 0 Newport TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2015-07-18   
423-720 1 Newport TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2015-11-16   
423-720 2 Newport TN   525E ONVOY, LLC - TN 474   2016-03-21   
423-720 3 Newport TN   525E ONVOY, LLC - TN 474   2016-03-21   
423-720 4 Newport TN   073H TELNYX LLC 474   2017-03-30   
423-720 5 Newport TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2025-10-17   
423-720 6 Newport TN   525E ONVOY, LLC - TN 474   2016-06-09   
423-720 7 Newport TN   525E ONVOY, LLC - TN 474   2016-06-09   
423-720 8 Newport TN   525E ONVOY, LLC - TN 474   2016-06-09   
423-720 9 Newport TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2017-12-02   

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

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