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: 991

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-991 A Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-991 0 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-991 1 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-991 2 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-14   
406-991 3 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-10-28   
406-991 4 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-991 6 Marion MT MSSLMTMACMD  6529 T-MOBILE USA, INC. 648   2024-06-09   
406-991 7 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2007-12-06   
406-991 8 Marion MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2011-03-05   
406-991 9 Marion MT   145J TERRA NOVA TELECOM INC. 648   2025-10-09   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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