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: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-678 A Roan Mountain TN JHCYTNXCXPX  525E ONVOY, LLC - TN 956      
423-678 0 Roan Mountain TN   525E ONVOY, LLC - TN 956   2021-06-15   
423-678 1 Roan Mountain TN   525E ONVOY, LLC - TN 956   2023-09-18   
423-678 2 Roan Mountain TN   624H ONVOY SPECTRUM, LLC 956   2024-03-05   
423-678 3 Roan Mountain TN   525E ONVOY, LLC - TN 956   2021-07-10   
423-678 4 Roan Mountain TN   525E ONVOY, LLC - TN 956   2021-07-10   
423-678 6 Roan Mountain TN   081J SKYBEST COMMUNICATIONS, INC. - TN 956   2024-08-25   
423-678 8 Roan Mountain TN   525E ONVOY, LLC - TN 956   2021-06-16   
423-678 9 Roan Mountain TN   124F BANDWIDTH.COM CLEC, LLC - TN 956   2025-12-20   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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