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: 630

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-630 A Sidney MT BLNGMTWE6MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650      
406-630 0 Sidney MT   073H TELNYX LLC 650   2017-03-31   
406-630 1 Sidney MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2016-09-10   
406-630 2 Sidney MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2013-04-30   
406-630 3 Sidney MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2021-12-04   
406-630 4 Sidney MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2005-04-09   
406-630 5 Sidney MT   453F ONVOY, LLC - MT 650   2006-10-20   
406-630 6 Sidney MT   453F ONVOY, LLC - MT 650   2019-09-15   
406-630 7 Sidney MT   453F ONVOY, LLC - MT 650   2011-10-24   
406-630 8 Sidney MT   588H AIRUS, INC. - MT 650   2018-03-02   
406-630 9 Sidney MT   588H AIRUS, INC. - MT 650   2020-03-27   

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

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