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: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-503 A Willcox AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-503 0 Willcox AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2021-07-02   
520-503 1 Willcox AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-503 2 Willcox AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-503 3 Willcox AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-503 4 Willcox AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-503 5 Willcox AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-503 6 Willcox AZ   939H COMMIO, LLC 668   2022-09-24   
520-503 7 Willcox AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2024-11-22   
520-503 8 Willcox AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2021-07-02   
520-503 9 Willcox AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 668   2021-02-20   

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

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