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: 901

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-901 A Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650      
406-901 0 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2022-01-14   
406-901 1 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2022-01-14   
406-901 2 Billings MT BLNGMTWE6MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2021-07-23   
406-901 3 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2022-01-14   
406-901 4 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2024-02-09   
406-901 5 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-11-17   
406-901 6 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-11-17   
406-901 7 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-11-17   
406-901 8 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-11-17   
406-901 9 Billings MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2021-06-14   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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