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: 820

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-820 A Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-820 1 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-820 2 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-820 3 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-820 4 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-02-11   
406-820 5 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-02-11   
406-820 6 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-820 7 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2007-12-06   
406-820 8 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2011-03-05   
406-820 9 Olney MT GRFLMTMAHMD  073H TELNYX LLC 648   2020-08-13   

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

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