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: 536

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-536 A Douglas AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668      
520-536 0 Douglas AZ   073H TELNYX LLC 668   2021-03-25   
520-536 1 Douglas AZ   630E ONVOY, LLC - AZ 668   2021-06-28   
520-536 2 Douglas AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-536 3 Douglas AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-536 4 Douglas AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-536 5 Douglas AZ   630E ONVOY, LLC - AZ 668   2021-02-19   
520-536 6 Douglas AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 668   2022-10-27   
520-536 8 Douglas AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 668   2021-05-28   
520-536 9 Douglas AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 668   2021-02-20   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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