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: 581

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-581 A Tombstone AZ TCSNAZMAXBY  515J IP HORIZON LLC 668      
520-581 0 Tombstone AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668   2023-04-24   
520-581 1 Tombstone AZ   515J IP HORIZON LLC 668   2021-10-25   
520-581 2 Tombstone AZ   630E ONVOY, LLC - AZ 668   2021-11-27   
520-581 4 Tombstone AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2022-06-10   
520-581 5 Tombstone AZ   630E ONVOY, LLC - AZ 668   2021-10-26   
520-581 6 Tombstone AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 668   2022-03-19   
520-581 7 Tombstone AZ   630E ONVOY, LLC - AZ 668   2022-02-20   
520-581 8 Tombstone AZ   630E ONVOY, LLC - AZ 668   2022-02-20   

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

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