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: 904

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-904 A Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472      
423-904 0 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2022-06-12   
423-904 1 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2021-09-26   
423-904 2 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2021-09-26   
423-904 3 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2021-09-26   
423-904 4 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2021-09-26   
423-904 5 Chattanooga TN   525E ONVOY, LLC - TN 472   2021-10-23   
423-904 6 Chattanooga TN   525E ONVOY, LLC - TN 472   2021-10-23   
423-904 7 Chattanooga TN   478J NUSO, LLC 472   2024-11-24   
423-904 8 Chattanooga TN   6214 NEW CINGULAR WIRELESS PCS, LLC - GA 472   2021-07-17   
423-904 9 Chattanooga TN   624H ONVOY SPECTRUM, LLC 472   2021-06-14   

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

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