Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-278 A Phoenix AZ PHNXAZ28VMD  073H TELNYX LLC 666      
623-278 0 Phoenix AZ   073H TELNYX LLC 666   2021-12-05   
623-278 1 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-12-06   
623-278 2 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 3 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 4 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 5 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 6 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 7 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 8 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   
623-278 9 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-12-06   

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

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