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: 285

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-285 A Three Forks MT THFKMTMARS1  9636 QWEST CORPORATION 650      
406-285 0 Three Forks MT   9636 QWEST CORPORATION 650      
406-285 1 Three Forks MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2009-02-13   
406-285 2 Three Forks MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2004-11-13   
406-285 3 Three Forks MT   9636 QWEST CORPORATION 650      
406-285 4 Three Forks MT   9636 QWEST CORPORATION 650      
406-285 5 Three Forks MT   9636 QWEST CORPORATION 650      
406-285 6 Three Forks MT   9636 QWEST CORPORATION 650      
406-285 7 Three Forks MT   453F ONVOY, LLC - MT 650   2007-03-19   
406-285 8 Three Forks MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2011-06-27   
406-285 9 Three Forks MT   9636 QWEST CORPORATION 650      

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

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