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: 438

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-438 A Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 0 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2026-10-29   
623-438 1 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2026-11-12   
623-438 2 Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 3 Phoenix AZ   490J BOOST SUBSCRIBERCO L.L.C. 666   2026-09-30   
623-438 4 Phoenix AZ   490J BOOST SUBSCRIBERCO L.L.C. 666   2026-10-10   
623-438 5 Phoenix AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2026-11-01   
623-438 6 Phoenix AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2026-11-01   
623-438 7 Phoenix AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2026-11-01   
623-438 8 Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 9 Phoenix AZ   883K AHOI LLC 666   2026-09-28   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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