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: 418

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-418 A Cooke City MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650      
406-418 0 Cooke City MT   073H TELNYX LLC 650   2019-10-21   
406-418 1 Cooke City MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-418 2 Cooke City MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-418 3 Cooke City MT   453F ONVOY, LLC - MT 650   2021-07-05   
406-418 4 Cooke City MT   453F ONVOY, LLC - MT 650   2019-10-20   
406-418 5 Cooke City MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-02-12   
406-418 6 Cooke City MT   453F ONVOY, LLC - MT 650   2019-10-20   
406-418 7 Cooke City MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-418 8 Cooke City MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-418 9 Cooke City MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-03-21   

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

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