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: 344

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-344 A Havre MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-344 0 Havre MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2018-01-12   
406-344 1 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-04-04   
406-344 2 Havre MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2018-01-20   
406-344 3 Havre MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2016-09-11   
406-344 4 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-344 5 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-01-03   
406-344 6 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-344 7 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-01-03   
406-344 8 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-10-28   
406-344 9 Havre MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2020-06-05   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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