Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Fort Defiance, AZ

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
928-729 A FTDFAZXCRS0  4449 NAVAJO COMM CO INC - AZ DBA FRONTIER NAVAJO COM 980      
928-730 A   6010 NEW CINGULAR WIRELESS PCS, LLC 980      
928-730 3 STMCAZXEXMD  3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 980   2020-03-27   
928-730 5 STMCAZXE6MD  6010 NEW CINGULAR WIRELESS PCS, LLC 980   2023-10-17   
928-730 6 STMCAZXE6MD  6010 NEW CINGULAR WIRELESS PCS, LLC 980   2023-10-17   
928-730 7 STMCAZXE7MD  073H TELNYX LLC 980   2022-07-29   
928-730 8 STMCAZXE6MD  6010 NEW CINGULAR WIRELESS PCS, LLC 980   2021-10-22   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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