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: 540

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-540 A Missoula MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-540 0 Missoula MT   453F ONVOY, LLC - MT 648   2019-11-18   
406-540 1 Missoula MT   453F ONVOY, LLC - MT 648      
406-540 2 Missoula MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2014-01-31   
406-540 3 Missoula MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2014-02-17   
406-540 4 Missoula MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2014-05-28   
406-540 5 Missoula MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-540 6 Missoula MT   453F ONVOY, LLC - MT 648   2019-06-20   
406-540 7 Missoula MT   453F ONVOY, LLC - MT 648   2012-08-25   
406-540 8 Missoula MT   453F ONVOY, LLC - MT 648   2019-11-18   
406-540 9 Missoula MT   453F ONVOY, LLC - MT 648   2019-11-18   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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