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: 308

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-308 A Cascade MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648      
406-308 0 Cascade MT   073H TELNYX LLC 648   2020-08-07   
406-308 1 Cascade MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-308 2 Cascade MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-308 3 Cascade MT   453F ONVOY, LLC - MT 648   2020-06-05   
406-308 4 Cascade MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-308 5 Cascade MT   453F ONVOY, LLC - MT 648   2019-10-28   
406-308 6 Cascade MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-308 7 Cascade MT   624H ONVOY SPECTRUM, LLC 648   2025-02-02   
406-308 8 Cascade MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-04-24   
406-308 9 Cascade MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2020-11-03   

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

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