Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-718 A GRFLMTMAPMD  506J TWILIO INTERNATIONAL, INC. 648      
406-718 1   792K CHARTER IP ENABLED SERVICES, LLC 648   2024-09-08   
406-718 4   506J TWILIO INTERNATIONAL, INC. 648   2022-08-28   
406-718 7   453F ONVOY, LLC - MT 648   2021-06-11   
406-718 8   453F ONVOY, LLC - MT 648   2021-06-11   
406-821 A DRBYMTMARS1  9636 QWEST CORPORATION 648      
406-821 0   9636 QWEST CORPORATION 648      
406-821 1   9636 QWEST CORPORATION 648      
406-821 2   9636 QWEST CORPORATION 648      
406-821 3   9636 QWEST CORPORATION 648      
406-821 4   9636 QWEST CORPORATION 648      
406-821 5   073H TELNYX LLC 648   2020-08-07   
406-821 6   453F ONVOY, LLC - MT 648   2007-03-19   
406-821 7   453F ONVOY, LLC - MT 648   2012-12-10   
406-821 8   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2020-05-06   
406-821 9   9636 QWEST CORPORATION 648      

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

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