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: 420

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-420 A Tucson AZ TCSMAZCHEMD  321J HD CARRIER LLC 668      
520-420 0 Tucson AZ   5562 METROPCS, INC. 668   2020-02-09   
520-420 1 Tucson AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 668   2020-03-06   
520-420 2 Tucson AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668   2020-03-09   
520-420 3 Tucson AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668   2020-03-09   
520-420 4 Tucson AZ   6529 T-MOBILE USA, INC. 668   2020-06-05   
520-420 5 Tucson AZ   6529 T-MOBILE USA, INC. 668   2020-06-05   
520-420 6 Tucson AZ   6529 T-MOBILE USA, INC. 668   2020-06-05   
520-420 7 Tucson AZ   6529 T-MOBILE USA, INC. 668   2020-06-05   
520-420 8 Tucson AZ   5562 METROPCS, INC. 668   2020-05-24   
520-420 9 Tucson AZ   321J HD CARRIER LLC 668   2020-02-08   

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

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