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: 743

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-743 A Laurel MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-743 0 Laurel MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-743 1 Laurel MT   453F ONVOY, LLC - MT 650   2021-07-05   
406-743 2 Laurel MT   453F ONVOY, LLC - MT 650   2021-07-05   
406-743 3 Laurel MT   453F ONVOY, LLC - MT 650   2017-05-29   
406-743 4 Laurel MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 650   2016-04-08   
406-743 5 Laurel MT   453F ONVOY, LLC - MT 650   2020-11-10   
406-743 6 Laurel MT   073H TELNYX LLC 650   2017-03-31   
406-743 7 Laurel MT   508J CENTURYLINK COMMUNICATIONS, LLC 650   2016-08-11   
406-743 8 Laurel MT   624H ONVOY SPECTRUM, LLC 650   2024-03-22   
406-743 9 Laurel MT   994E BANDWIDTH.COM CLEC, LLC - MT 650   2020-12-18   

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

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