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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
406-866 3 Great Falls MT ULM MTMARS1  9636 QWEST CORPORATION 648      
406-866 6 Great Falls MT GRFLMTMA69Z  490J BOOST SUBSCRIBERCO L.L.C. 648   2023-08-21   
406-866 8 Great Falls MT GRFLMTMAGMD  6529 T-MOBILE USA, INC. 648   2023-10-23   
406-867 A Billings MT BLNGMT93IMD  700J WAVENATION, LLC 650      
406-867 0 Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-867 1 Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-867 2 Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-867 3 Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-867 4 Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-867 5 Billings MT BLNGMT93IMD  700J WAVENATION, LLC 650   2026-02-03   
406-867 6 Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-867 7 Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-867 8 Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-867 9 Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2022-11-12   
406-868 A Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-869 A Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-870 A Great Falls MT GRFLMTMA5MD  994E BANDWIDTH.COM CLEC, LLC - MT 648      
406-870 0 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-870 1 Great Falls MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-870 2 Great Falls MT GRFLMTMA5MD  994E BANDWIDTH.COM CLEC, LLC - MT 648   2025-10-27   
406-871 A Kalispell MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-872 A Polson MT PLSNMTPC1MD  986F WESTERN MONTANA COMMUNITYTEL INC. - MT 648      
406-872 0 Polson MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-15   
406-872 1 Polson MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-15   
406-872 2 Polson MT PLSNMTPC1MD  986F WESTERN MONTANA COMMUNITYTEL INC. - MT 648   2007-12-06   
406-872 3 Polson MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-15   
406-872 4 Polson MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-15   
406-872 5 Polson MT MSSLMTMACMD  6529 T-MOBILE USA, INC. 648   2025-02-23   
406-872 6 Polson MT HLNAMTMAUMD  508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   
406-872 7 Polson MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2011-03-05   
406-873 A Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 0 Cut Bank MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2006-07-03   
406-873 1 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2006-10-19   
406-873 2 Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 3 Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 4 Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 5 Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 6 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-873 7 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-07-05   
406-873 8 Cut Bank MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2005-02-21   
406-873 9 Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-874 A Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 3 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 5 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 6 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 7 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 8 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-874 9 Miles City MT MLCYMTBVDS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-875 A Pompeys Pillar MT WRDNMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-876 A Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      

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

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