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: 731

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-731 A Great Falls MT   700J WAVENATION, LLC 648      
406-731 0 Great Falls MT   700J WAVENATION, LLC 648   2025-10-05   
406-731 1 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 2 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 3 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 4 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 5 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 6 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 7 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-731 8 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648   2004-07-12   

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

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