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: 235

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-235 A Wolf Creek MT WLCKMTMARS1  9636 QWEST CORPORATION 648      
406-235 0 Wolf Creek MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2011-04-21   
406-235 1 Wolf Creek MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2006-11-08   
406-235 2 Wolf Creek MT   145J TERRA NOVA TELECOM INC. 648   2025-10-09   
406-235 3 Wolf Creek MT   453F ONVOY, LLC - MT 648   2023-08-20   
406-235 4 Wolf Creek MT   9636 QWEST CORPORATION 648      
406-235 5 Wolf Creek MT   073H TELNYX LLC 648   2020-08-13   
406-235 6 Wolf Creek MT   624H ONVOY SPECTRUM, LLC 648   2025-01-02   
406-235 7 Wolf Creek MT   453F ONVOY, LLC - MT 648   2007-03-19   
406-235 8 Wolf Creek MT   073H TELNYX LLC 648   2022-01-18   
406-235 9 Wolf Creek MT   9636 QWEST CORPORATION 648      

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

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.