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: 872

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-872 A Chattanooga TN   145J TERRA NOVA TELECOM INC. 472      
423-872 0 Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472   2023-08-15   
423-872 2 Chattanooga TN CHTGTNNSXKY  525E ONVOY, LLC - TN 472   2023-09-02   
423-872 3 Chattanooga TN CHTGTNNSXNZ  197D VONAGE AMERICA LLC 472   2023-10-13   
423-872 5 Chattanooga TN   145J TERRA NOVA TELECOM INC. 472   2025-12-07   
423-872 6 Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472   2023-08-15   
423-872 7 Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472   2023-08-15   
423-872 8 Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472   2023-08-15   
423-872 9 Chattanooga TN CHTGTNNSXMZ  624H ONVOY SPECTRUM, LLC 472   2023-08-15   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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