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: 545

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-545 A Madisonville TN KNVLTNMANMD  4806 LEVEL 3 COMMUNICATIONS, LLC - TN 474      
423-545 0 Madisonville TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2022-01-16   
423-545 1 Madisonville TN   073H TELNYX LLC 474   2022-06-26   
423-545 2 Madisonville TN   525E ONVOY, LLC - TN 474   2022-09-29   
423-545 3 Madisonville TN   516C AT&T CORP. 474   2010-06-17   
423-545 4 Madisonville TN   4806 LEVEL 3 COMMUNICATIONS, LLC - TN 474      
423-545 5 Madisonville TN   525E ONVOY, LLC - TN 474   2021-10-25   
423-545 6 Madisonville TN   525E ONVOY, LLC - TN 474   2021-10-25   
423-545 7 Madisonville TN   525E ONVOY, LLC - TN 474   2022-09-29   
423-545 8 Madisonville TN   792K CHARTER IP ENABLED SERVICES, LLC 474   2012-05-31   
423-545 9 Madisonville TN   792K CHARTER IP ENABLED SERVICES, LLC 474   2005-11-27   

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

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