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: 718

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-718 A Darby MT GRFLMTMAPMD  506J TWILIO INTERNATIONAL, INC. 648      
406-718 1 Darby MT   792K CHARTER IP ENABLED SERVICES, LLC 648   2024-09-08   
406-718 4 Darby MT   506J TWILIO INTERNATIONAL, INC. 648   2022-08-28   
406-718 7 Darby MT   453F ONVOY, LLC - MT 648   2021-06-11   
406-718 8 Darby MT   453F ONVOY, LLC - MT 648   2021-06-11   

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

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