Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 287

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-287 A Whitehall MT WHTHMTMARS1  9636 QWEST CORPORATION 648      
406-287 0 Whitehall MT   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 648   2017-08-07   
406-287 1 Whitehall MT   453F ONVOY, LLC - MT 648   2021-07-08   
406-287 2 Whitehall MT   9636 QWEST CORPORATION 648      
406-287 3 Whitehall MT   9636 QWEST CORPORATION 648      
406-287 4 Whitehall MT   624H ONVOY SPECTRUM, LLC 648   2025-02-03   
406-287 5 Whitehall MT   9636 QWEST CORPORATION 648      
406-287 6 Whitehall MT   453F ONVOY, LLC - MT 648   2011-10-24   
406-287 7 Whitehall MT   9636 QWEST CORPORATION 648      
406-287 8 Whitehall MT   453F ONVOY, LLC - MT 648   2007-03-19   
406-287 9 Whitehall MT   9636 QWEST CORPORATION 648      

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

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