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: 324

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-324 A Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 0 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2024-06-22   
406-324 1 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 2 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 3 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 4 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 5 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 6 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-324 7 Helena MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2006-05-27   
406-324 8 Helena MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2025-02-12   
406-324 9 Helena MT GRFLMTMAHMD  073H TELNYX LLC 648   2020-08-13   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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