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: 749

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-749 A Colstrip MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-749 0 Colstrip MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-749 1 Colstrip MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-749 2 Colstrip MT   145J TERRA NOVA TELECOM INC. 650   2021-09-28   
406-749 3 Colstrip MT   145J TERRA NOVA TELECOM INC. 650   2023-06-24   
406-749 4 Colstrip MT   145J TERRA NOVA TELECOM INC. 650   2022-05-05   
406-749 5 Colstrip MT FRSYMTMA0MD  8140 RANGE TELEPHONE COOPERATIVE, INC. - MT 650   2023-12-12   
406-749 7 Colstrip MT   145J TERRA NOVA TELECOM INC. 650   2025-05-08   
406-749 8 Colstrip MT BLNGMTWE9MD  073H TELNYX LLC 650   2024-09-12   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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