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: 659

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-659 A North Parkman MT DNRHWYMARS1  9636 QWEST CORPORATION 654      
406-659 5 North Parkman MT   624H ONVOY SPECTRUM, LLC 654   2021-11-14   
406-659 6 North Parkman MT   508J CENTURYLINK COMMUNICATIONS, LLC 654   2015-03-18   
406-659 7 North Parkman MT   453F ONVOY, LLC - MT 654   2011-10-24   
406-659 8 North Parkman MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 654   2023-03-02   
406-659 9 North Parkman MT   9636 QWEST CORPORATION 654      

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

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