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: 266

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-266 A Sierra Vista AZ TCSMAZOI3MD  6529 T-MOBILE USA, INC. 668      
520-266 0 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 1 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 2 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 3 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 4 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 5 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 6 Sierra Vista AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 668   2024-02-03   
520-266 7 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 8 Sierra Vista AZ   6529 T-MOBILE USA, INC. 668      
520-266 9 Sierra Vista AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 668   2008-10-23   

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

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