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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-307 A Canyon Creek MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2025-05-02   
406-307 1 Canyon Creek MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2025-05-02   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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