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: 823

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-823 A Livingston MT LVTNMTMADS0  9636 QWEST CORPORATION 650      
406-823 0 Livingston MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2009-02-13   
406-823 1 Livingston MT   746D MONTANA OPTICOM, LLC - MT 650   2010-08-16   
406-823 2 Livingston MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-823 3 Livingston MT   453F ONVOY, LLC - MT 650   2012-12-17   
406-823 4 Livingston MT   453F ONVOY, LLC - MT 650   2012-12-17   
406-823 5 Livingston MT   453F ONVOY, LLC - MT 650   2020-01-05   
406-823 6 Livingston MT   9636 QWEST CORPORATION 650      
406-823 7 Livingston MT   145J TERRA NOVA TELECOM INC. 650   2021-09-28   
406-823 8 Livingston MT   453F ONVOY, LLC - MT 650   2011-10-24   
406-823 9 Livingston MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2013-05-26   

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

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