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.

NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 881

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-881 A Olney MT OLNYMTXCRS0  2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      
406-881 0 Olney MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2021-07-05   
406-881 1 Olney MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-02-27   
406-881 2 Olney MT OLNYMTXCRS0  2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      
406-881 4 Olney MT OLNYMTXCRS0  2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.