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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-423 A Casa Grande AZ CSGRAZMADS0  9636 QWEST CORPORATION 666      
520-423 0 Casa Grande AZ   9636 QWEST CORPORATION 666      
520-423 1 Casa Grande AZ   9636 QWEST CORPORATION 666      
520-423 2 Casa Grande AZ   9636 QWEST CORPORATION 666      
520-423 3 Casa Grande AZ   630E ONVOY, LLC - AZ 666   2003-09-13   
520-423 4 Casa Grande AZ   7175 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 666   2003-09-28   
520-423 5 Casa Grande AZ   630E ONVOY, LLC - AZ 666   2005-01-31   
520-423 6 Casa Grande AZ   630E ONVOY, LLC - AZ 666   2008-03-02   
520-423 7 Casa Grande AZ   6529 T-MOBILE USA, INC. 666   2008-04-12   
520-423 8 Casa Grande AZ   9636 QWEST CORPORATION 666      
520-423 9 Casa Grande AZ   9636 QWEST CORPORATION 666   2007-03-19   

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

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