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: 391

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-391 A Cut Bank MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-391 1 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-10-31   
406-391 2 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2023-04-02   
406-391 6 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2024-04-28   
406-391 7 Cut Bank MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-03-28   

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

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