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: 502

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-502 A Helena MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-502 1 Helena MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2012-06-01   
406-502 2 Helena MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2014-04-30   
406-502 8 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-12-13   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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