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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
406-308 0 Cascade MT   073H TELNYX LLC 648   2020-08-07   
406-308 1 Cascade MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-308 2 Cascade MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-308 3 Cascade MT   453F ONVOY, LLC - MT 648   2020-06-05   
406-308 4 Cascade MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-308 5 Cascade MT   453F ONVOY, LLC - MT 648   2019-10-28   
406-308 6 Cascade MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-308 7 Cascade MT   624H ONVOY SPECTRUM, LLC 648   2025-02-02   
406-308 8 Cascade MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-04-24   
406-308 9 Cascade MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2020-11-03   
406-309 A Kalispell MT KLSLMTAZ1MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-309 0 Kalispell MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2013-03-12   
406-309 1 Kalispell MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2013-03-12   
406-309 2 Kalispell MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2011-12-01   
406-309 3 Kalispell MT   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 648   2019-02-14   
406-309 4 Kalispell MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2012-09-10   
406-309 5 Kalispell MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2012-10-06   
406-309 6 Kalispell MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2018-08-26   
406-309 7 Kalispell MT   073H TELNYX LLC 648   2020-08-13   
406-309 8 Kalispell MT   453F ONVOY, LLC - MT 648   2019-02-19   
406-309 9 Kalispell MT   453F ONVOY, LLC - MT 648   2019-02-19   
406-310 A Butte MT BUTTMTAQ2MD  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-310 0 Butte MT   145J TERRA NOVA TELECOM INC. 648   2025-10-09   
406-310 1 Butte MT   6529 T-MOBILE USA, INC. 648   2024-07-07   
406-310 2 Butte MT   6529 T-MOBILE USA, INC. 648   2024-04-04   
406-310 3 Butte MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-310 4 Butte MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2021-05-14   
406-310 5 Butte MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-310 6 Butte MT   6529 T-MOBILE USA, INC. 648   2021-02-07   
406-310 7 Butte MT   5562 METROPCS, INC. 648   2017-07-22   
406-310 8 Butte MT   5562 METROPCS, INC. 648   2017-07-22   
406-310 9 Butte MT   6529 T-MOBILE USA, INC. 648   2019-09-14   
406-312 A Bozeman MT BLNGMT93AMD  478J NUSO, LLC 650      
406-312 0 Bozeman MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-312 1 Bozeman MT   588H AIRUS, INC. - MT 650   2019-04-29   
406-312 2 Bozeman MT   478J NUSO, LLC 650   2020-07-17   
406-312 3 Bozeman MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-312 4 Bozeman MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2025-02-10   
406-312 5 Bozeman MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2020-05-10   
406-312 6 Bozeman MT   453F ONVOY, LLC - MT 650   2019-01-05   
406-312 7 Bozeman MT   453F ONVOY, LLC - MT 650   2019-01-05   
406-312 8 Bozeman MT   588H AIRUS, INC. - MT 650   2019-12-05   
406-312 9 Bozeman MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2020-05-10   
406-313 A Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-313 0 Boulder MT   453F ONVOY, LLC - MT 648   2013-01-17   
406-313 1 Boulder MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2019-06-14   
406-313 2 Boulder MT   453F ONVOY, LLC - MT 648   2020-04-04   
406-313 3 Boulder MT   453F ONVOY, LLC - MT 648   2019-10-28   
406-313 4 Boulder MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-313 5 Boulder MT   453F ONVOY, LLC - MT 648   2020-02-23   

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

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