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   2008-07-19   
406-417 1 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2014-09-05   
406-417 3 Helena MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2019-01-05   
406-417 5 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2023-11-20   
406-417 6 Helena MT MSSLMTMAYMD  771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2014-11-20   
406-417 7 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2022-03-26   
406-417 8 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2021-03-06   
406-417 9 Helena MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2019-12-21   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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