Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 7830 MID-RIVERS TELEPHONE COOPERATIVE, INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
406-228 7 Glasgow MT   650   2019-04-09   
406-234 A Miles City MT MLCYMTBVDS0  650      
406-345 A Glendive MT GLNDMTAJRS0  650      
406-345 2 Glendive MT   650      
406-345 3 Glendive MT   650      
406-345 7 Glendive MT   650      
406-345 8 Glendive MT   650      
406-345 9 Glendive MT   650      
406-377 A Glendive MT GLNDMTAJRS0  650      
406-433 A Sidney MT SDNYMTAORS0  650      
406-488 A Sidney MT SDNYMTAORS0  650      
406-535 A Lewistown MT LWTWMTAQRS1  648      
406-742 A Fairview MT FRVWMTMARS2  650      
406-742 5 Fairview MT   650      
406-742 9 Fairview MT   650      
406-789 8 Medicine Lake MT   650   2019-12-16   
406-796 A Wibaux MT WIBXMTAARS0  650      
406-796 2 Wibaux MT   650      
406-796 9 Wibaux MT   650      
406-874 A Miles City MT MLCYMTBVDS0  650      
406-874 3 Miles City MT   650      
406-874 5 Miles City MT   650      
406-874 6 Miles City MT   650      
406-874 7 Miles City MT   650      
406-874 8 Miles City MT   650      
406-874 9 Miles City MT   650      
406-894 7 Billings MT   650   2019-02-28   
701-844 A East Fairview ND FRVWMTMARS2  650      

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

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