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: 537

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-537 A Phoenix AZ AGFIAZSRDS0  9636 QWEST CORPORATION 666      
623-537 0 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 1 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 2 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 3 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 4 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 5 Phoenix AZ   9636 QWEST CORPORATION 666   2005-01-25   
623-537 6 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 7 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2005-03-30   
623-537 8 Phoenix AZ   9636 QWEST CORPORATION 666      
623-537 9 Phoenix AZ   9636 QWEST CORPORATION 666      

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

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