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: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-231 A Whitlow AZ PHNXAZMAXQX  587F BANDWIDTH.COM CLEC, LLC - AZ 666      
520-231 0 Whitlow AZ   073H TELNYX LLC 666   2018-05-01   
520-231 1 Whitlow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2018-05-17   
520-231 2 Whitlow AZ   630E ONVOY, LLC - AZ 666   2016-05-03   
520-231 3 Whitlow AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2017-02-24   
520-231 4 Whitlow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2018-07-07   
520-231 5 Whitlow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2016-05-09   
520-231 6 Whitlow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2018-10-05   
520-231 7 Whitlow AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 666   2019-06-19   
520-231 8 Whitlow AZ   630E ONVOY, LLC - AZ 666   2019-07-11   
520-231 9 Whitlow AZ   073H TELNYX LLC 666   2019-05-20   

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

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