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: 873

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-873 A Cut Bank MT CTBNMTMARS1  9636 QWEST CORPORATION 648      
406-873 0 Cut Bank MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-07-03   
406-873 1 Cut Bank MT   453F ONVOY, LLC - MT 648   2006-10-19   
406-873 2 Cut Bank MT   9636 QWEST CORPORATION 648      
406-873 3 Cut Bank MT   9636 QWEST CORPORATION 648      
406-873 4 Cut Bank MT   9636 QWEST CORPORATION 648      
406-873 5 Cut Bank MT   9636 QWEST CORPORATION 648      
406-873 6 Cut Bank MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-873 7 Cut Bank MT   453F ONVOY, LLC - MT 648   2021-07-05   
406-873 8 Cut Bank MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2005-02-21   
406-873 9 Cut Bank MT   9636 QWEST CORPORATION 648      

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

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