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: 402

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-402 A Great Falls MT GRFLMTMAGMD  6529 T-MOBILE USA, INC. 648      
406-402 0 Great Falls MT   6529 T-MOBILE USA, INC. 648   2022-04-02   
406-402 1 Great Falls MT   6529 T-MOBILE USA, INC. 648   2025-08-29   
406-402 2 Great Falls MT   6529 T-MOBILE USA, INC. 648   2021-07-07   
406-402 3 Great Falls MT   5562 METROPCS, INC. 648   2018-06-24   
406-402 4 Great Falls MT   6529 T-MOBILE USA, INC. 648   2022-09-29   
406-402 5 Great Falls MT   6529 T-MOBILE USA, INC. 648   2021-04-15   
406-402 6 Great Falls MT   6529 T-MOBILE USA, INC. 648   2020-02-06   
406-402 7 Great Falls MT   6529 T-MOBILE USA, INC. 648   2019-04-12   
406-402 8 Great Falls MT   6529 T-MOBILE USA, INC. 648   2018-10-08   
406-402 9 Great Falls MT   6529 T-MOBILE USA, INC. 648   2017-11-15   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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