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: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-631 A Elmo MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-631 0 Elmo MT   073H TELNYX LLC 648   2020-08-09   
406-631 1 Elmo MT   453F ONVOY, LLC - MT 648   2012-12-10   
406-631 2 Elmo MT   453F ONVOY, LLC - MT 648   2012-12-10   
406-631 3 Elmo MT   453F ONVOY, LLC - MT 648   2012-12-10   
406-631 4 Elmo MT   986F WESTERN MONTANA COMMUNITYTEL INC. - MT 648   2013-07-20   
406-631 5 Elmo MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-631 6 Elmo MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-631 7 Elmo MT   453F ONVOY, LLC - MT 648   2007-09-21   
406-631 8 Elmo MT   453F ONVOY, LLC - MT 648   2011-04-06   
406-631 9 Elmo MT   453F ONVOY, LLC - MT 648   2021-03-07   

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

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