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: 398

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-398 A Phoenix AZ PHNAAZ55DS1  4793 XO ARIZONA, INC. 666      
623-398 0 Phoenix AZ   4793 XO ARIZONA, INC. 666      
623-398 1 Phoenix AZ   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 666      
623-398 2 Phoenix AZ   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 666      
623-398 3 Phoenix AZ   4793 XO ARIZONA, INC. 666      
623-398 4 Phoenix AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2004-05-02   
623-398 5 Phoenix AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2004-05-02   
623-398 6 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-08-17   
623-398 7 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-08-17   
623-398 8 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-08-17   
623-398 9 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2006-03-09   

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

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