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: 997

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-997 A Fromberg MT BLNGMTWEMMD  7421 AT&T - LOCAL 650   2024-03-09   
406-997 0 Fromberg MT BLNGMTWEDMD  624H ONVOY SPECTRUM, LLC 650   2024-03-22   
406-997 7 Fromberg MT BLNGMT939MD  145J TERRA NOVA TELECOM INC. 650   2024-04-22   
406-997 9 Fromberg MT BLNGMTWEMMD  7421 AT&T - LOCAL 650   2024-03-09   

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

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