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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
406-602 8 Bozeman MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2020-08-08   
406-602 9 Bozeman MT   588H AIRUS, INC. - MT 650   2021-04-19   
406-603 A Helena MT HLNAMTHO3MD  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-603 0 Helena MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2014-07-12   
406-603 4 Helena MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2013-12-30   
406-604 A Great Falls MT GRFLMTMARS0  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-604 0 Great Falls MT   453F ONVOY, LLC - MT 648   2019-01-22   
406-604 1 Great Falls MT   453F ONVOY, LLC - MT 648   2019-01-22   
406-604 2 Great Falls MT   624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 3 Great Falls MT   624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 4 Great Falls MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2011-09-11   
406-604 5 Great Falls MT   624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 6 Great Falls MT   624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 7 Great Falls MT   508J CENTURYLINK COMMUNICATIONS, LLC 648   2016-02-11   
406-604 8 Great Falls MT   453F ONVOY, LLC - MT 648   2019-01-22   
406-604 9 Great Falls MT   073H TELNYX LLC 648   2023-08-25   
406-605 A Butte MT MSSLMTMAEMD  073H TELNYX LLC 648      
406-605 0 Butte MT   073H TELNYX LLC 648   2021-06-09   
406-605 1 Butte MT   624H ONVOY SPECTRUM, LLC 648   2023-11-27   
406-605 2 Butte MT   624H ONVOY SPECTRUM, LLC 648   2023-11-27   
406-605 3 Butte MT   453F ONVOY, LLC - MT 648   2024-04-06   
406-605 4 Butte MT   490J DISH WIRELESS, LLC 648   2023-12-18   
406-605 5 Butte MT   624H ONVOY SPECTRUM, LLC 648   2021-10-30   
406-605 6 Butte MT   624H ONVOY SPECTRUM, LLC 648   2021-10-30   
406-605 7 Butte MT   624H ONVOY SPECTRUM, LLC 648   2021-10-30   
406-605 8 Butte MT   624H ONVOY SPECTRUM, LLC 648   2021-10-30   
406-605 9 Butte MT   624H ONVOY SPECTRUM, LLC 648   2023-11-27   
406-606 A Billings MT BLNGMTMATMD  935G TRI TEL, INC. - MT 650      
406-606 0 Billings MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2014-11-02   
406-606 1 Billings MT   935G TRI TEL, INC. - MT 650   2013-01-28   
406-606 2 Billings MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2014-11-14   
406-606 3 Billings MT   624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-606 4 Billings MT   453F ONVOY, LLC - MT 650   2019-07-08   
406-606 5 Billings MT   624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-606 6 Billings MT   453F ONVOY, LLC - MT 650   2019-07-08   
406-606 7 Billings MT   624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-606 8 Billings MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-10-09   
406-606 9 Billings MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-10-09   
406-607 A Kalispell MT KLSLMTXC4MD  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-607 0 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2016-06-05   
406-607 1 Kalispell MT   6529 T-MOBILE USA, INC. 648   2021-04-06   
406-607 2 Kalispell MT   6529 T-MOBILE USA, INC. 648   2022-02-25   
406-607 3 Kalispell MT   6529 T-MOBILE USA, INC. 648   2022-03-15   
406-607 4 Kalispell MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2013-12-30   
406-607 5 Kalispell MT   6529 T-MOBILE USA, INC. 648   2020-03-27   
406-607 6 Kalispell MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-607 7 Kalispell MT   6529 T-MOBILE USA, INC. 648   2018-10-30   
406-607 8 Kalispell MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-607 9 Kalispell MT   6529 T-MOBILE USA, INC. 648   2019-08-02   
406-608 A Billings MT BLNGMTASKMD  515J IP HORIZON LLC 650      

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

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