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: 571

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-571 A Finley Point MT KLSLMTAZ1MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-571 1 Finley Point MT   453F ONVOY, LLC - MT 648   2012-12-17   
406-571 2 Finley Point MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-04-21   
406-571 3 Finley Point MT   453F ONVOY, LLC - MT 648   2016-02-26   
406-571 4 Finley Point MT   453F ONVOY, LLC - MT 648   2016-02-26   
406-571 5 Finley Point MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-571 6 Finley Point MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-571 7 Finley Point MT   453F ONVOY, LLC - MT 648   2007-04-14   
406-571 8 Finley Point MT   453F ONVOY, LLC - MT 648   2011-07-11   
406-571 9 Finley Point MT   073H TELNYX LLC 648   2020-08-09   

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

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