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: 512

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-512 A Boulder MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-512 0 Boulder MT GRFLMTMAHMD  073H TELNYX LLC 648   2023-07-16   
406-512 1 Boulder MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-04-25   
406-512 2 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2023-04-26   
406-512 8 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2023-08-20   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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