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: 918

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-918 A Libby MT   6010 NEW CINGULAR WIRELESS PCS, LLC 960   2026-03-14   
406-918 9 Libby MT   6010 NEW CINGULAR WIRELESS PCS, LLC 960   2026-03-14   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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