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: 456

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-456 A La Follette TN KNVLTNMAY5X  073H TELNYX LLC 474      
423-456 0 La Follette TN   073H TELNYX LLC 474   2021-07-25   
423-456 1 La Follette TN   5562 METROPCS, INC. 474   2021-08-28   
423-456 2 La Follette TN   525E ONVOY, LLC - TN 474   2021-10-25   
423-456 3 La Follette TN   525E ONVOY, LLC - TN 474   2019-10-30   
423-456 4 La Follette TN   525E ONVOY, LLC - TN 474   2021-07-30   
423-456 5 La Follette TN   525E ONVOY, LLC - TN 474   2021-03-19   
423-456 6 La Follette TN   073H TELNYX LLC 474   2017-03-30   
423-456 7 La Follette TN   525E ONVOY, LLC - TN 474   2021-03-04   
423-456 8 La Follette TN   525E ONVOY, LLC - TN 474   2022-04-11   
423-456 9 La Follette TN   525E ONVOY, LLC - TN 474   2020-12-21   

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

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