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: 388

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-388 A Phoenix AZ CRCYAZNMRS1  9636 QWEST CORPORATION 666      
623-388 0 Phoenix AZ   9636 QWEST CORPORATION 666      
623-388 1 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2006-03-09   
623-388 2 Phoenix AZ   9636 QWEST CORPORATION 666      
623-388 3 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-04-12   
623-388 4 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-04-12   
623-388 5 Phoenix AZ   9636 QWEST CORPORATION 666      
623-388 6 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2004-04-12   
623-388 7 Phoenix AZ   5562 METROPCS, INC. 666   2005-04-03   
623-388 8 Phoenix AZ   9636 QWEST CORPORATION 666      
623-388 9 Phoenix AZ   9636 QWEST CORPORATION 666      

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

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