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: 888

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-888 A West Glacier MT WGLCMTMARS1  9636 QWEST CORPORATION 648      
406-888 0 West Glacier MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-888 1 West Glacier MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2023-04-24   
406-888 2 West Glacier MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-888 3 West Glacier MT   073H TELNYX LLC 648   2020-08-13   
406-888 4 West Glacier MT   508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   
406-888 5 West Glacier MT   9636 QWEST CORPORATION 648      
406-888 6 West Glacier MT   453F ONVOY, LLC - MT 648   2007-04-14   
406-888 7 West Glacier MT   9636 QWEST CORPORATION 648      
406-888 8 West Glacier MT   453F ONVOY, LLC - MT 648   2011-07-17   
406-888 9 West Glacier MT   9636 QWEST CORPORATION 648      

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

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