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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-307 A Phoenix AZ PHNXAZ28X6X  710A ALLO COMMUNICATIONS, LLC - NE 666      
623-307 0 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 1 Phoenix AZ   710A ALLO COMMUNICATIONS, LLC - NE 666   2023-06-18   
623-307 2 Phoenix AZ   624H ONVOY SPECTRUM, LLC 666   2023-07-12   
623-307 3 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2023-11-21   
623-307 4 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 5 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 6 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 7 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 8 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   
623-307 9 Phoenix AZ   630E ONVOY, LLC - AZ 666   2023-06-26   

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

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