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: 616

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-616 A Three Forks MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650      
406-616 0 Three Forks MT   453F ONVOY, LLC - MT 650   2020-11-10   
406-616 1 Three Forks MT   453F ONVOY, LLC - MT 650   2012-12-17   
406-616 2 Three Forks MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2014-03-31   
406-616 3 Three Forks MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-06-05   
406-616 4 Three Forks MT   453F ONVOY, LLC - MT 650   2019-09-15   
406-616 5 Three Forks MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 650   2020-08-24   
406-616 6 Three Forks MT   624H ONVOY SPECTRUM, LLC 650   2025-02-17   
406-616 7 Three Forks MT   453F ONVOY, LLC - MT 650   2011-08-22   
406-616 8 Three Forks MT   073H TELNYX LLC 650   2018-07-25   
406-616 9 Three Forks MT   453F ONVOY, LLC - MT 650   2021-02-11   

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

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