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: 614

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-614 A Bigfork MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-614 0 Bigfork MT   073H TELNYX LLC 648   2020-12-31   
406-614 1 Bigfork MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-614 2 Bigfork MT   986F WESTERN MONTANA COMMUNITYTEL INC. - MT 648   2021-03-26   
406-614 3 Bigfork MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2023-01-08   
406-614 4 Bigfork MT   453F ONVOY, LLC - MT 648   2021-03-28   
406-614 5 Bigfork MT   453F ONVOY, LLC - MT 648   2021-03-28   
406-614 6 Bigfork MT   453F ONVOY, LLC - MT 648   2020-12-13   
406-614 7 Bigfork MT   624H ONVOY SPECTRUM, LLC 648   2021-07-18   
406-614 8 Bigfork MT   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-614 9 Bigfork MT   624H ONVOY SPECTRUM, LLC 648   2021-11-14   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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