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: 866

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-866 A Great Falls MT ULM MTMARS1  9636 QWEST CORPORATION 648      
406-866 0 Great Falls MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2006-03-13   
406-866 1 Great Falls MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2024-04-28   
406-866 2 Great Falls MT ULM MTMARS1  9636 QWEST CORPORATION 648      
406-866 3 Great Falls MT ULM MTMARS1  9636 QWEST CORPORATION 648      
406-866 6 Great Falls MT GRFLMTMA69Z  490J DISH WIRELESS, LLC 648   2023-08-21   
406-866 8 Great Falls MT GRFLMTMAGMD  6529 T-MOBILE USA, INC. 648   2023-10-23   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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