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: 285

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-285 A Nogales AZ NGLSAZMARS1  9636 QWEST CORPORATION 668      
520-285 0 Nogales AZ   9636 QWEST CORPORATION 668      
520-285 1 Nogales AZ   6529 T-MOBILE USA, INC. 668   2024-08-10   
520-285 2 Nogales AZ   9636 QWEST CORPORATION 668      
520-285 3 Nogales AZ   9636 QWEST CORPORATION 668      
520-285 4 Nogales AZ   9636 QWEST CORPORATION 668      
520-285 5 Nogales AZ   9636 QWEST CORPORATION 668      
520-285 6 Nogales AZ   6529 T-MOBILE USA, INC. 668   2006-08-11   
520-285 7 Nogales AZ   6529 T-MOBILE USA, INC. 668   2006-10-10   
520-285 8 Nogales AZ   630E ONVOY, LLC - AZ 668   2022-08-25   
520-285 9 Nogales AZ   6529 T-MOBILE USA, INC. 668   2006-02-24   

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

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