Local Calling Guide

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Search area code/prefix (NPA/NXX)
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Dutton, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-476 A DTTNMTMARS1  9636 QWEST CORPORATION 648      
406-476 0   073H TELNYX LLC 648   2020-08-09   
406-476 1   453F ONVOY, LLC - MT 648   2012-12-17   
406-476 2   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2017-10-20   
406-476 3   9636 QWEST CORPORATION 648      
406-476 4   624H ONVOY SPECTRUM, LLC 648   2025-02-02   
406-476 5   453F ONVOY, LLC - MT 648   2011-10-21   
406-476 6   453F ONVOY, LLC - MT 648   2020-11-08   
406-476 7   453F ONVOY, LLC - MT 648   2007-03-19   
406-476 8   453F ONVOY, LLC - MT 648   2021-03-07   
406-476 9   453F ONVOY, LLC - MT 648   2021-03-07   

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

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