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
406-407 6 Kalispell MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2010-10-26   
406-407 7 Kalispell MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2011-07-01   
406-407 8 Kalispell MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2011-07-08   
406-407 9 Kalispell MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-04-26   
406-408 A Hays MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-408 0 Hays MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2019-11-29   
406-409 A Billings MT BLNGMTASX0X  425J CSC WIRELESS, LLC 650      
406-409 0 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2021-01-17   
406-409 1 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2021-04-22   
406-409 2 Billings MT BLNGMTASX0X  425J CSC WIRELESS, LLC 650   2019-07-20   
406-409 3 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-409 4 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2019-09-15   
406-409 5 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2023-01-24   
406-409 6 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2024-01-26   
406-409 7 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-409 8 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2020-10-26   
406-409 9 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2020-10-26   
406-410 A Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-410 0 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-410 1 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-410 2 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2022-12-10   
406-410 3 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2021-06-04   
406-410 4 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-10-29   
406-410 5 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-12-07   
406-410 6 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2023-01-06   
406-410 7 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2023-01-06   
406-410 8 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-08-24   
406-410 9 Helena MT MSSLMTXC3MD  939H COMMIO, LLC 648   2023-08-17   
406-412 A Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650      
406-412 0 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 1 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 2 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 3 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 4 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 5 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 6 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 7 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 8 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-412 9 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2017-06-21   
406-413 A Billings MT BLNGMTMADS1  9636 QWEST CORPORATION 650      
406-413 0 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-04-09   
406-413 1 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-04-09   
406-413 2 Billings MT BLNGMTMADS1  9636 QWEST CORPORATION 650   2015-06-11   
406-413 3 Billings MT BLNGMTMADS1  9636 QWEST CORPORATION 650   2015-06-11   
406-413 4 Billings MT BLNGMTMADS1  9636 QWEST CORPORATION 650   2015-06-11   
406-413 5 Billings MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650   2016-11-18   
406-413 6 Billings MT BLNGMTWEBMD  771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 650   2017-08-21   
406-413 7 Billings MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-08-13   
406-413 8 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-04-09   
406-413 9 Billings MT BLNGMT93DS0  588H AIRUS, INC. - MT 650   2017-04-06   

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Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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