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: 966

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-966 A Shelby MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-966 0 Shelby MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-966 1 Shelby MT   453F ONVOY, LLC - MT 648   2012-12-17   
406-966 2 Shelby MT   453F ONVOY, LLC - MT 648   2012-12-17   
406-966 3 Shelby MT   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 648   2014-03-14   
406-966 4 Shelby MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-966 5 Shelby MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-966 6 Shelby MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-966 7 Shelby MT   508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   

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

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