Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-604 A Great Falls MT GRFLMTMARS0  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-604 0 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-01-22   
406-604 1 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-01-22   
406-604 2 Great Falls MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 3 Great Falls MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 4 Great Falls MT GRFLMTMARS0  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2011-09-11   
406-604 5 Great Falls MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 6 Great Falls MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-05-22   
406-604 7 Great Falls MT HLNAMTMAUMD  508J CENTURYLINK COMMUNICATIONS, LLC 648   2016-02-11   
406-604 8 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-01-22   
406-604 9 Great Falls MT GRFLMTMAHMD  073H TELNYX LLC 648   2023-08-25   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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