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: 751

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-751 A Kalispell MT KLSLMTXCDS0  2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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