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: 970

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-970 A Billings MT BLNGMTWE8MD  508J CENTURYLINK COMMUNICATIONS, LLC 650      
406-970 0 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2019-04-26   
406-970 1 Billings MT BLNGMTWECMD  551G NUSO, LLC 650   2017-10-17   
406-970 2 Billings MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-10-22   
406-970 3 Billings MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2020-05-13   
406-970 4 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-08-22   
406-970 5 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-08-22   
406-970 6 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-08-22   
406-970 7 Billings MT BLNGMTWE8MD  508J CENTURYLINK COMMUNICATIONS, LLC 650   2016-08-01   
406-970 8 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-06-11   
406-970 9 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2021-06-11   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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