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: 607

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-607 A Kalispell MT KLSLMTXC4MD  7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648      
406-607 0 Kalispell MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2016-06-05   
406-607 1 Kalispell MT   6529 T-MOBILE USA, INC. 648   2021-04-06   
406-607 2 Kalispell MT   6529 T-MOBILE USA, INC. 648   2022-02-25   
406-607 3 Kalispell MT   6529 T-MOBILE USA, INC. 648   2022-03-15   
406-607 4 Kalispell MT   7870 BLACKFOOT COMMUNICATIONS, INC. - MT 648   2013-12-30   
406-607 5 Kalispell MT   6529 T-MOBILE USA, INC. 648   2020-03-27   
406-607 6 Kalispell MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-607 7 Kalispell MT   6529 T-MOBILE USA, INC. 648   2018-10-30   
406-607 8 Kalispell MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-607 9 Kalispell MT   6529 T-MOBILE USA, INC. 648   2019-08-02   

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

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