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: 417

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-417 A Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 0 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 1 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-417 3 Helena MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-417 4 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 5 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 6 Helena MT MSSLMTMAYMD  771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648      
406-417 7 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648      
406-417 8 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-417 9 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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