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: 316

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-316 A Boulder MT   453F ONVOY, LLC - MT 648      
406-316 0 Boulder MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-316 1 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-04-22   
406-316 2 Boulder MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-07-18   
406-316 3 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-06-05   
406-316 4 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-11-08   
406-316 5 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-05-15   
406-316 6 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-08-28   
406-316 7 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-10-11   
406-316 8 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-11-18   

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

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