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: 356

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-356 A Forsyth MT FRSYMTMARS1  9636 QWEST CORPORATION 650      
406-356 0 Forsyth MT   453F ONVOY, LLC - MT 650   2019-09-15   
406-356 1 Forsyth MT   073H TELNYX LLC 650   2018-07-25   
406-356 2 Forsyth MT   9636 QWEST CORPORATION 650      
406-356 3 Forsyth MT   9636 QWEST CORPORATION 650      
406-356 4 Forsyth MT   9636 QWEST CORPORATION 650      
406-356 5 Forsyth MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2006-05-21   
406-356 6 Forsyth MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2009-02-13   
406-356 7 Forsyth MT   9636 QWEST CORPORATION 650      
406-356 8 Forsyth MT   453F ONVOY, LLC - MT 650   2007-04-14   
406-356 9 Forsyth MT   9636 QWEST CORPORATION 650      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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