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: 501

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-501 A Whitehall MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648      
406-501 0 Whitehall MT   453F ONVOY, LLC - MT 648   2020-04-04   
406-501 1 Whitehall MT   073H TELNYX LLC 648   2020-08-13   
406-501 2 Whitehall MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2020-10-31   
406-501 3 Whitehall MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-501 4 Whitehall MT   453F ONVOY, LLC - MT 648   2019-10-20   
406-501 5 Whitehall MT   453F ONVOY, LLC - MT 648   2019-10-20   
406-501 6 Whitehall MT   453F ONVOY, LLC - MT 648   2020-01-03   
406-501 7 Whitehall MT   771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2020-08-24   
406-501 8 Whitehall MT   453F ONVOY, LLC - MT 648   2021-02-11   
406-501 9 Whitehall MT   453F ONVOY, LLC - MT 648   2021-02-11   

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

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