Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: GRFLMTMA7MD

<< 1 2 3 4 5 6

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-964 6 Great Falls MT 453F ONVOY, LLC - MT 648   2020-10-05   
406-966 1 Shelby MT 453F ONVOY, LLC - MT 648   2012-12-17   
406-966 2 Shelby MT 453F ONVOY, LLC - MT 648   2012-12-17   
406-966 5 Shelby MT 453F ONVOY, LLC - MT 648   2021-03-07   
406-966 6 Shelby MT 453F ONVOY, LLC - MT 648   2021-03-07   
406-980 6 Townsend MT 453F ONVOY, LLC - MT 648   2021-03-07   
406-980 8 Townsend MT 453F ONVOY, LLC - MT 648   2020-11-08   
406-982 0 Yellow Bay MT 453F ONVOY, LLC - MT 648   2021-07-08   
406-988 6 Dillon MT 453F ONVOY, LLC - MT 648   2021-03-07   
406-988 7 Dillon MT 453F ONVOY, LLC - MT 648   2006-10-19   
406-988 8 Dillon MT 453F ONVOY, LLC - MT 648   2021-03-07   
406-991 A Marion MT 453F ONVOY, LLC - MT 648      
406-991 0 Marion MT 453F ONVOY, LLC - MT 648   2012-12-14   
406-991 1 Marion MT 453F ONVOY, LLC - MT 648   2012-12-14   
406-991 2 Marion MT 453F ONVOY, LLC - MT 648   2012-12-14   
406-991 3 Marion MT 453F ONVOY, LLC - MT 648   2019-10-28   
406-991 4 Marion MT 453F ONVOY, LLC - MT 648   2019-09-15   
406-991 7 Marion MT 453F ONVOY, LLC - MT 648   2007-12-06   
406-991 8 Marion MT 453F ONVOY, LLC - MT 648   2011-03-05   
406-992 A Helena MT 453F ONVOY, LLC - MT 648      
406-992 0 Helena MT 453F ONVOY, LLC - MT 648   2025-05-17   

<< 1 2 3 4 5 6

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

Sponsored by: LES.NET

Like this site? We accept donations via PayPal.