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: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-251 A Casa Grande AZ TEMPAZNR5MD  6529 T-MOBILE USA, INC. 666      
520-251 0 Casa Grande AZ   6529 T-MOBILE USA, INC. 666      
520-251 1 Casa Grande AZ   5562 METROPCS, INC. 666      
520-251 2 Casa Grande AZ   5562 METROPCS, INC. 666      
520-251 3 Casa Grande AZ   5562 METROPCS, INC. 666      
520-251 4 Casa Grande AZ   6529 T-MOBILE USA, INC. 666   2015-12-18   
520-251 5 Casa Grande AZ   318J COMCAST IP PHONE, LLC 666   2012-01-02   
520-251 6 Casa Grande AZ   6529 T-MOBILE USA, INC. 666      
520-251 7 Casa Grande AZ   5562 METROPCS, INC. 666   2014-10-20   
520-251 8 Casa Grande AZ   6529 T-MOBILE USA, INC. 666   2007-03-12   
520-251 9 Casa Grande AZ   630E ONVOY, LLC - AZ 666   2015-04-23   

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

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