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: 403

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-403 A Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-403 0 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2006-05-08   
406-403 1 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-04-09   
406-403 2 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-07-06   
406-403 3 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-09-14   
406-403 4 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-10-22   
406-403 5 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-10-22   
406-403 6 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-11-23   
406-403 7 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2009-03-22   
406-403 8 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2009-11-23   
406-403 9 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2010-04-05   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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