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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-310 A Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 0 Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 1 Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 2 Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 3 Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 4 Phoenix AZ   630E ONVOY, LLC - AZ 666   2026-10-11   
623-310 5 Phoenix AZ   890G INTRADO COMMUNICATIONS, LLC 666   2026-10-12   
623-310 6 Phoenix AZ   890G INTRADO COMMUNICATIONS, LLC 666   2026-10-12   
623-310 7 Phoenix AZ   890G INTRADO COMMUNICATIONS, LLC 666   2026-10-12   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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