Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 928 [Rate centres in NPA 928] [Dial plan for NPA 928]

NXX: 544

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
928-544 A Castle Rock AZ PHNXAZ19AMD  965H FRACTEL, LLC 666      
928-544 0 Castle Rock AZ   579F PEERLESS NETWORK OF ARIZONA, LLC - AZ 666   2020-09-25   
928-544 1 Castle Rock AZ   073H TELNYX LLC 666   2020-10-03   
928-544 2 Castle Rock AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2025-06-26   
928-544 3 Castle Rock AZ   630E ONVOY, LLC - AZ 666   2020-11-24   
928-544 4 Castle Rock AZ   965H FRACTEL, LLC 666   2020-08-01   
928-544 5 Castle Rock AZ   624H ONVOY SPECTRUM, LLC 666   2020-11-03   
928-544 6 Castle Rock AZ   630E ONVOY, LLC - AZ 666   2021-01-16   
928-544 7 Castle Rock AZ   630E ONVOY, LLC - AZ 666   2021-01-16   
928-544 8 Castle Rock AZ   630E ONVOY, LLC - AZ 666   2021-01-16   
928-544 9 Castle Rock AZ   630E ONVOY, LLC - AZ 666   2021-01-16   

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

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