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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
406-318 2 Billings MT   073H TELNYX LLC 650   2023-01-09   
406-318 3 Billings MT   145J TERRA NOVA TELECOM INC. 650   2023-06-24   
406-318 4 Billings MT   6529 T-MOBILE USA, INC. 650   2024-10-11   
406-318 5 Billings MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-01-04   
406-318 6 Billings MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-01-04   
406-318 7 Billings MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-01-04   
406-318 8 Billings MT   453F ONVOY, LLC - MT 650   2015-12-10   
406-318 9 Billings MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-06-29   
406-319 A Polson MT MSSLMTEH4MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-319 0 Polson MT   6529 T-MOBILE USA, INC. 648   2023-12-16   
406-319 1 Polson MT   073H TELNYX LLC 648   2020-08-13   
406-319 2 Polson MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-04-17   
406-319 3 Polson MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-319 4 Polson MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-319 5 Polson MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-319 6 Polson MT   453F ONVOY, LLC - MT 648   2007-03-08   
406-319 8 Polson MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-319 9 Polson MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-320 A Roundup MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-320 0 Roundup MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-320 1 Roundup MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-320 2 Roundup MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-320 3 Roundup MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2019-10-10   
406-321 A Columbus MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 0 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 1 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 2 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 3 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 4 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-321 5 Columbus MT   453F ONVOY, LLC - MT 650   2021-02-11   
406-321 6 Columbus MT   453F ONVOY, LLC - MT 650   2021-02-11   
406-321 7 Columbus MT   145J TERRA NOVA TELECOM INC. 650   2021-09-28   
406-321 8 Columbus MT   588H AIRUS, INC. - MT 650   2020-07-20   
406-321 9 Columbus MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-322 A Columbus MT CLMBMTMARS1  9636 QWEST CORPORATION 650      
406-322 0 Columbus MT   9636 QWEST CORPORATION 650      
406-322 1 Columbus MT   9636 QWEST CORPORATION 650      
406-322 2 Columbus MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2004-11-13   
406-322 3 Columbus MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2006-01-06   
406-322 4 Columbus MT   9636 QWEST CORPORATION 650      
406-322 5 Columbus MT   9636 QWEST CORPORATION 650      
406-322 6 Columbus MT   9636 QWEST CORPORATION 650      
406-322 7 Columbus MT   939H COMMIO, LLC 650   2024-03-04   
406-322 8 Columbus MT   9636 QWEST CORPORATION 650      
406-322 9 Columbus MT   9636 QWEST CORPORATION 650      
406-323 A Roundup MT RNDPMTXCDS0  2246 MID-RIVERS TEL. COOP., INC. 650      
406-323 1 Roundup MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-323 2 Roundup MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-323 3 Roundup MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-323 4 Roundup MT   2246 MID-RIVERS TEL. COOP., INC. 650      

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

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