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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-310 A Butte MT BUTTMTAQ2MD  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-310 0 Butte MT   145J TERRA NOVA TELECOM INC. 648   2025-10-09   
406-310 1 Butte MT   6529 T-MOBILE USA, INC. 648   2024-07-07   
406-310 2 Butte MT   6529 T-MOBILE USA, INC. 648   2024-04-04   
406-310 3 Butte MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-310 4 Butte MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2021-05-14   
406-310 5 Butte MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-310 6 Butte MT   6529 T-MOBILE USA, INC. 648   2021-02-07   
406-310 7 Butte MT   5562 METROPCS, INC. 648   2017-07-22   
406-310 8 Butte MT   5562 METROPCS, INC. 648   2017-07-22   
406-310 9 Butte MT   6529 T-MOBILE USA, INC. 648   2019-09-14   

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

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