Local Calling Guide

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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-313 6 Boulder MT   453F ONVOY, LLC - MT 648   2013-01-17   
406-313 7 Boulder MT   508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   
406-313 8 Boulder MT   453F ONVOY, LLC - MT 648   2020-04-04   
406-313 9 Boulder MT   073H TELNYX LLC 648   2020-08-07   
406-314 A Kalispell MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-314 0 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2004-12-12   
406-314 1 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2005-01-31   
406-314 2 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2005-08-11   
406-314 3 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2005-09-26   
406-314 4 Kalispell MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-03-04   
406-314 5 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2006-03-20   
406-314 6 Kalispell MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2014-05-13   
406-314 7 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2018-09-21   
406-314 8 Kalispell MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2012-03-28   
406-314 9 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2015-10-29   
406-315 A Great Falls MT   443B SAGEBRUSH CELLULAR, INC. 648      
406-315 0 Great Falls MT   073H TELNYX LLC 648   2021-03-04   
406-315 1 Great Falls MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2011-03-10   
406-315 2 Great Falls MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2011-11-17   
406-315 3 Great Falls MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2012-05-06   
406-315 4 Great Falls MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-315 5 Great Falls MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-315 6 Great Falls MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-315 7 Great Falls MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-315 8 Great Falls MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2014-04-30   
406-315 9 Great Falls MT   443B SAGEBRUSH CELLULAR, INC. 648   2017-11-05   
406-316 A Boulder MT   453F ONVOY, LLC - MT 648      
406-316 0 Boulder MT   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-316 1 Boulder MT   453F ONVOY, LLC - MT 648   2021-04-22   
406-316 2 Boulder MT   624H ONVOY SPECTRUM, LLC 648   2021-07-18   
406-316 3 Boulder MT   453F ONVOY, LLC - MT 648   2020-06-05   
406-316 4 Boulder MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-316 5 Boulder MT   453F ONVOY, LLC - MT 648   2021-05-15   
406-316 6 Boulder MT   453F ONVOY, LLC - MT 648   2021-08-28   
406-316 7 Boulder MT   453F ONVOY, LLC - MT 648   2021-10-11   
406-316 8 Boulder MT   453F ONVOY, LLC - MT 648   2021-11-18   
406-317 A Missoula MT GRFLMTMAHMD  073H TELNYX LLC 648      
406-317 0 Missoula MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2019-09-10   
406-317 1 Missoula MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2012-05-06   
406-317 2 Missoula MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2013-03-12   
406-317 3 Missoula MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2013-03-12   
406-317 4 Missoula MT   073H TELNYX LLC 648   2020-01-16   
406-317 5 Missoula MT   453F ONVOY, LLC - MT 648   2021-02-19   
406-317 6 Missoula MT   453F ONVOY, LLC - MT 648   2021-02-19   
406-317 7 Missoula MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2020-09-19   
406-317 8 Missoula MT   453F ONVOY, LLC - MT 648   2021-02-19   
406-317 9 Missoula MT   453F ONVOY, LLC - MT 648   2021-02-19   
406-318 A Billings MT   453F ONVOY, LLC - MT 650   2025-03-23   
406-318 0 Billings MT   145J TERRA NOVA TELECOM INC. 650   2025-09-09   
406-318 1 Billings MT   145J TERRA NOVA TELECOM INC. 650   2024-12-05   

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

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