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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
406-373 7 Billings MT   9636 QWEST CORPORATION 650      
406-373 8 Billings MT   9636 QWEST CORPORATION 650   2004-11-22   
406-373 9 Billings MT   9636 QWEST CORPORATION 650      
406-374 A Moore MT FTBNMTXCDS0  3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-375 A Hamilton MT HMTNMTMADS0  9636 QWEST CORPORATION 648      
406-375 0 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 1 Hamilton MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-06-30   
406-375 2 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 3 Hamilton MT   453F ONVOY, LLC - MT 648   2022-09-19   
406-375 4 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 5 Hamilton MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-05-17   
406-375 6 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 7 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 8 Hamilton MT   9636 QWEST CORPORATION 648      
406-375 9 Hamilton MT   9636 QWEST CORPORATION 648      
406-376 A Gildford MT HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-377 A Glendive MT GLNDMTAJRS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-378 A Big Sandy MT HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 0 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 1 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 2 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 3 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 4 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 5 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 6 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 7 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 8 Big Sandy MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2024-10-17   
406-378 9 Big Sandy MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-379 A Turner MT HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-380 A Lewistown MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-380 0 Lewistown MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-380 1 Lewistown MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2021-04-22   
406-380 2 Lewistown MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2011-08-08   
406-380 3 Lewistown MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-380 4 Lewistown MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-380 5 Lewistown MT   453F ONVOY, LLC - MT 648   2022-12-04   
406-380 7 Lewistown MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-380 8 Lewistown MT   073H TELNYX LLC 648   2020-08-13   
406-380 9 Lewistown MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-381 A Hamilton MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-382 A Superior MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-382 0 Superior MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-382 1 Superior MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-10-10   
406-382 3 Superior MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2016-06-27   
406-382 9 Superior MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2018-04-05   
406-383 A Dodson MT FTBNMTXCDS0  3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-384 A Billings MT BLNGMT20PS0  4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-384 0 Billings MT   4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      
406-384 1 Billings MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2023-04-06   
406-384 2 Billings MT   4222 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 650      

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

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