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: 668

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-668 A Fromberg MT FRMBMTMARS1  9636 QWEST CORPORATION 650      
406-668 0 Fromberg MT BLNGMTWE6MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2004-11-13   
406-668 1 Fromberg MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2009-02-13   
406-668 2 Fromberg MT BLNGMTMATMD  935G TRI TEL, INC. - MT 650   2013-01-28   
406-668 3 Fromberg MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-05-31   
406-668 4 Fromberg MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2011-10-20   
406-668 5 Fromberg MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2023-08-20   
406-668 6 Fromberg MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2007-03-19   
406-668 7 Fromberg MT FRMBMTMARS1  9636 QWEST CORPORATION 650      
406-668 8 Fromberg MT BLNGMTWE8MD  508J CENTURYLINK COMMUNICATIONS, LLC 650   2016-08-11   
406-668 9 Fromberg MT FRMBMTMARS1  9636 QWEST CORPORATION 650      

Last updated: Fri, 28 Jun 2024 03:14:50 UTC

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