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: 690

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-690 A Morristown TN KNVNTNEC0MD  073H TELNYX LLC 474      
423-690 0 Morristown TN   6673 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TN 474   2018-08-24   
423-690 1 Morristown TN   073H TELNYX LLC 474   2017-01-23   
423-690 2 Morristown TN   525E ONVOY, LLC - TN 474   2021-03-19   
423-690 3 Morristown TN   114F TELEPORT COMMUNICATIONS AMERICA, LLC - TN 474   2017-02-10   
423-690 4 Morristown TN   525E ONVOY, LLC - TN 474   2021-03-19   
423-690 5 Morristown TN   525E ONVOY, LLC - TN 474   2021-03-19   
423-690 6 Morristown TN   525E ONVOY, LLC - TN 474   2021-03-04   
423-690 7 Morristown TN   525E ONVOY, LLC - TN 474   2020-12-21   
423-690 8 Morristown TN   525E ONVOY, LLC - TN 474   2019-06-23   
423-690 9 Morristown TN   525E ONVOY, LLC - TN 474   2019-06-23   

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

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