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: 732

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-732 A St Mary MT STMYMTMARS1  9636 QWEST CORPORATION 648      
406-732 0 St Mary MT   073H TELNYX LLC 648   2020-08-13   
406-732 1 St Mary MT   624H ONVOY SPECTRUM, LLC 648   2020-11-08   
406-732 2 St Mary MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-732 3 St Mary MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2014-05-24   
406-732 4 St Mary MT   9636 QWEST CORPORATION 648      
406-732 5 St Mary MT   9636 QWEST CORPORATION 648      
406-732 6 St Mary MT   453F ONVOY, LLC - MT 648   2007-03-19   
406-732 7 St Mary MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-732 8 St Mary MT   453F ONVOY, LLC - MT 648   2011-10-24   
406-732 9 St Mary MT   9636 QWEST CORPORATION 648      

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

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