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: 965

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-965 A Great Falls MT GRFLMTMADS3  588H AIRUS, INC. - MT 648      
406-965 1 Great Falls MT GRFLMTMADS3  588H AIRUS, INC. - MT 648   2023-11-26   
406-965 2 Great Falls MT VGHNMTMARS1  9636 QWEST CORPORATION 648      
406-965 3 Great Falls MT VGHNMTMARS1  9636 QWEST CORPORATION 648      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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