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: 790

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-790 A Culbertson MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-790 0 Culbertson MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-790 1 Culbertson MT   145J TERRA NOVA TELECOM INC. 650   2026-01-04   
406-790 4 Culbertson MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2023-07-31   
406-790 5 Culbertson MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2022-12-21   
406-790 9 Culbertson MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2020-07-26   

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

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