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: 597

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-597 A Superior AZ PHNXAZ28DS3  630E ONVOY, LLC - AZ 666      
520-597 0 Superior AZ   630E ONVOY, LLC - AZ 666   2016-07-31   
520-597 1 Superior AZ   630E ONVOY, LLC - AZ 666   2016-07-31   
520-597 2 Superior AZ   630E ONVOY, LLC - AZ 666   2020-03-30   
520-597 3 Superior AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 666   2018-10-26   
520-597 4 Superior AZ   630E ONVOY, LLC - AZ 666   2019-07-11   
520-597 5 Superior AZ   630E ONVOY, LLC - AZ 666   2019-07-11   
520-597 6 Superior AZ   7217 TELEPORT COMMUNICATIONS AMERICA, LLC - AZ 666   2019-01-14   
520-597 7 Superior AZ   630E ONVOY, LLC - AZ 666   2016-05-16   
520-597 8 Superior AZ   630E ONVOY, LLC - AZ 666   2016-05-16   
520-597 9 Superior AZ   073H TELNYX LLC 666   2017-06-09   

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

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