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: 866

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-866 A Phoenix AZ PHNXAZMYDS0  9636 QWEST CORPORATION 666      
623-866 0 Phoenix AZ   9636 QWEST CORPORATION 666      
623-866 1 Phoenix AZ   9636 QWEST CORPORATION 666      
623-866 2 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2005-08-08   
623-866 3 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2005-08-08   
623-866 4 Phoenix AZ   9636 QWEST CORPORATION 666   2003-09-17   
623-866 5 Phoenix AZ   9636 QWEST CORPORATION 666   2003-09-17   
623-866 6 Phoenix AZ   9636 QWEST CORPORATION 666   2003-09-17   
623-866 7 Phoenix AZ   9636 QWEST CORPORATION 666   2003-09-17   
623-866 8 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2005-08-08   
623-866 9 Phoenix AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2005-08-08   

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

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