Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 520 [Rate centres in NPA 520] [Dial plan for NPA 520]

NXX: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-837 A Tucson AZ TCSNAZMAXKX  7217 TELEPORT COMMUNICATIONS AMERICA, LLC - AZ 668      
520-837 0 Tucson AZ   7217 TELEPORT COMMUNICATIONS AMERICA, LLC - AZ 668      
520-837 1 Tucson AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 668   2010-06-18   
520-837 2 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 3 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 4 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 5 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 6 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 7 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 8 Tucson AZ   9636 QWEST CORPORATION 668   2005-07-28   
520-837 9 Tucson AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2008-10-30   

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

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