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: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-304 A Missoula MT MSSLMTMACMD  6529 T-MOBILE USA, INC. 648      
406-304 0 Missoula MT   6529 T-MOBILE USA, INC. 648   2020-12-20   
406-304 1 Missoula MT   6529 T-MOBILE USA, INC. 648   2020-09-21   
406-304 2 Missoula MT   6529 T-MOBILE USA, INC. 648   2020-01-16   
406-304 3 Missoula MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2016-12-15   
406-304 4 Missoula MT   6529 T-MOBILE USA, INC. 648   2019-04-26   
406-304 5 Missoula MT   6529 T-MOBILE USA, INC. 648   2018-12-07   
406-304 6 Missoula MT   6529 T-MOBILE USA, INC. 648   2018-01-12   
406-304 7 Missoula MT   6529 T-MOBILE USA, INC. 648   2017-04-10   
406-304 8 Missoula MT   6529 T-MOBILE USA, INC. 648   2017-04-10   
406-304 9 Missoula MT   6529 T-MOBILE USA, INC. 648   2016-06-30   

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

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