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: 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   453F ONVOY, LLC - MT 648   2021-07-05   
406-881 1 Olney MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-02-27   
406-881 2 Olney MT   2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      
406-881 4 Olney MT   2249 CENTURYTEL OF MONTANA, INC. DBA CENTURYLINK 648      

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

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