Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Boulder, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-225 A BLDRMTMARS1  9636 QWEST CORPORATION 648      
406-225 0   453F ONVOY, LLC - MT 648   2012-12-10   
406-225 1   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-225 3   9636 QWEST CORPORATION 648      
406-225 4   9636 QWEST CORPORATION 648      
406-225 5   145J TERRA NOVA TELECOM INC. 648   2025-10-09   
406-225 6   453F ONVOY, LLC - MT 648   2022-10-29   
406-225 7   453F ONVOY, LLC - MT 648   2007-03-19   
406-225 8   453F ONVOY, LLC - MT 648   2022-10-29   
406-225 9   9636 QWEST CORPORATION 648      
406-313 A GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-313 0   453F ONVOY, LLC - MT 648   2013-01-17   
406-313 1   792K CHARTER IP ENABLED SERVICES, LLC 648   2019-06-14   
406-313 2   453F ONVOY, LLC - MT 648   2020-04-04   
406-313 3   453F ONVOY, LLC - MT 648   2019-10-28   
406-313 4   453F ONVOY, LLC - MT 648   2020-01-03   
406-313 5   453F ONVOY, LLC - MT 648   2020-02-23   
406-313 6   453F ONVOY, LLC - MT 648   2013-01-17   
406-313 7   508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   
406-313 8   453F ONVOY, LLC - MT 648   2020-04-04   
406-313 9   073H TELNYX LLC 648   2020-08-07   
406-316 A   453F ONVOY, LLC - MT 648      
406-316 0   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-316 1   453F ONVOY, LLC - MT 648   2021-04-22   
406-316 2   624H ONVOY SPECTRUM, LLC 648   2021-07-18   
406-316 3   453F ONVOY, LLC - MT 648   2020-06-05   
406-316 4   453F ONVOY, LLC - MT 648   2020-11-08   
406-316 5   453F ONVOY, LLC - MT 648   2021-05-15   
406-316 6   453F ONVOY, LLC - MT 648   2021-08-28   
406-316 7   453F ONVOY, LLC - MT 648   2021-10-11   
406-316 8   453F ONVOY, LLC - MT 648   2021-11-18   
406-512 A MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-512 0   073H TELNYX LLC 648   2023-07-16   
406-512 1   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-04-25   
406-512 2   453F ONVOY, LLC - MT 648   2023-04-26   
406-512 8   453F ONVOY, LLC - MT 648   2023-08-20   

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

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