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: 996

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-996 A Helena MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-996 1 Helena MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2011-03-10   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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