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: 988

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-988 A Dillon MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-988 0 Dillon MT HLNAMTHH5MD  792K CHARTER IP ENABLED SERVICES, LLC 648   2006-03-24   
406-988 4 Dillon MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2005-03-02   
406-988 6 Dillon MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-03-07   
406-988 7 Dillon MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2006-10-19   
406-988 8 Dillon MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-03-07   

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

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