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: 989

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-989 A West Glendive MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-989 0 West Glendive MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-989 1 West Glendive MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-989 9 West Glendive MT   145J TERRA NOVA TELECOM INC. 650   2025-06-07   

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

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