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: 689

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-689 A Wisdom MT WSDMMTXCDS0  2254 SOUTHERN MONTANA TEL. CO. 648      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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