Local Calling Guide

Area code/prefix search

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Shelby, MT

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-966 5 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-03-07   
406-966 6 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-03-07   
406-966 7 HLNAMTMAUMD  508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   

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Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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