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: 760

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-760 A Great Falls MT MSSLMTMAGMD  197D VONAGE AMERICA LLC 648      
406-760 0 Great Falls MT   197D VONAGE AMERICA LLC 648   2018-08-11   
406-760 1 Great Falls MT   453F ONVOY, LLC - MT 648      
406-760 2 Great Falls MT   453F ONVOY, LLC - MT 648   2022-11-17   
406-760 4 Great Falls MT   6529 T-MOBILE USA, INC. 648   2024-07-25   
406-760 8 Great Falls MT   6529 T-MOBILE USA, INC. 648   2022-02-08   

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

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