Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 430

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-430 A Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-430 0 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-05-17   
406-430 1 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-430 2 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-10-28   
406-430 3 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-11-18   
406-430 4 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-430 5 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-11-18   
406-430 6 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-430 7 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-11-18   
406-430 8 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-11-18   
406-430 9 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-11-30   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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