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: 268

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-268 A Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 0 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 1 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 2 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 3 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 5 Great Falls MT   520K TDS METROCOM, LLC 648   2025-11-17   
406-268 6 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 7 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 8 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      
406-268 9 Great Falls MT GRFLMTMADS0  9636 QWEST CORPORATION 648      

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

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