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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
406-415 7 Deer Lodge MT   453F ONVOY, LLC - MT 648   2011-10-21   
406-415 8 Deer Lodge MT   453F ONVOY, LLC - MT 648   2019-10-28   
406-415 9 Deer Lodge MT   073H TELNYX LLC 648   2020-08-07   
406-416 A Forsyth MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650      
406-416 0 Forsyth MT   453F ONVOY, LLC - MT 650   2021-07-05   
406-416 1 Forsyth MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2021-12-23   
406-416 2 Forsyth MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-416 3 Forsyth MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2023-06-01   
406-416 4 Forsyth MT   453F ONVOY, LLC - MT 650   2020-08-08   
406-416 5 Forsyth MT   453F ONVOY, LLC - MT 650   2020-08-08   
406-416 6 Forsyth MT   453F ONVOY, LLC - MT 650   2020-11-10   
406-416 7 Forsyth MT   453F ONVOY, LLC - MT 650   2020-11-10   
406-416 8 Forsyth MT   939H COMMIO, LLC 650   2022-06-06   
406-416 9 Forsyth MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2022-12-13   
406-417 A Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 0 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2008-07-19   
406-417 1 Helena MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2014-09-05   
406-417 2 Helena MT   624H ONVOY SPECTRUM, LLC 648   2025-01-02   
406-417 3 Helena MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2019-01-05   
406-417 4 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2024-11-30   
406-417 5 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2023-11-20   
406-417 6 Helena MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2014-11-20   
406-417 7 Helena MT   6529 T-MOBILE USA, INC. 648   2022-03-26   
406-417 8 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2021-03-06   
406-417 9 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2019-12-21   
406-418 A Cooke City MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650      
406-418 0 Cooke City MT   073H TELNYX LLC 650   2019-10-21   
406-418 1 Cooke City MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-418 2 Cooke City MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-418 3 Cooke City MT   453F ONVOY, LLC - MT 650   2021-07-05   
406-418 4 Cooke City MT   453F ONVOY, LLC - MT 650   2019-10-20   
406-418 5 Cooke City MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-02-12   
406-418 6 Cooke City MT   453F ONVOY, LLC - MT 650   2019-10-20   
406-418 7 Cooke City MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-418 8 Cooke City MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-418 9 Cooke City MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-03-21   
406-419 A Victor MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2025-01-13   
406-419 0 Victor MT   073H TELNYX LLC 648   2020-08-13   
406-419 1 Victor MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2021-05-01   
406-419 2 Victor MT   453F ONVOY, LLC - MT 648   2021-07-08   
406-419 4 Victor MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-419 5 Victor MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-419 6 Victor MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-420 A Bigfork MT KLSLMTAZ1MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-420 0 Bigfork MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2020-06-09   
406-420 1 Bigfork MT   453F ONVOY, LLC - MT 648   2020-01-13   
406-420 2 Bigfork MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-04-21   
406-420 3 Bigfork MT   453F ONVOY, LLC - MT 648   2012-12-10   
406-420 4 Bigfork MT   453F ONVOY, LLC - MT 648   2012-12-10   
406-420 5 Bigfork MT   453F ONVOY, LLC - MT 648   2012-12-10   

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

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