Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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St Mary, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-732 A STMYMTMARS1  9636 QWEST CORPORATION 648      
406-732 0 GRFLMTMAHMD  073H TELNYX LLC 648   2020-08-13   
406-732 1 GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2020-11-08   
406-732 2 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-732 3 MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2014-05-24   
406-732 4 STMYMTMARS1  9636 QWEST CORPORATION 648      
406-732 5 STMYMTMARS1  9636 QWEST CORPORATION 648      
406-732 6 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2007-03-19   
406-732 7 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2019-09-15   
406-732 8 GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2011-10-24   
406-732 9 STMYMTMARS1  9636 QWEST CORPORATION 648      

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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