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: 374

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-374 A La Follette TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474      
423-374 0 La Follette TN   525E ONVOY, LLC - TN 474      
423-374 1 La Follette TN   525E ONVOY, LLC - TN 474      
423-374 2 La Follette TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2019-08-09   
423-374 3 La Follette TN   525E ONVOY, LLC - TN 474   2021-02-25   
423-374 4 La Follette TN   525E ONVOY, LLC - TN 474   2021-02-25   
423-374 5 La Follette TN   525E ONVOY, LLC - TN 474   2021-02-25   
423-374 6 La Follette TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2021-01-10   
423-374 7 La Follette TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2021-01-10   
423-374 8 La Follette TN   525E ONVOY, LLC - TN 474   2021-02-25   
423-374 9 La Follette TN   124F BANDWIDTH.COM CLEC, LLC - TN 474   2025-09-06   

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

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