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: 945

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-945 A Havre MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 0 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 1 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 2 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 3 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 4 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 5 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-945 7 Havre MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2006-06-08   
406-945 8 Havre MT   145J TERRA NOVA TELECOM INC. 648   2025-10-11   
406-945 9 Havre MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2008-11-21   

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

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