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: 289

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-289 A Conrad MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-289 0 Conrad MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-289 1 Conrad MT   453F ONVOY, LLC - MT 648   2023-08-20   
406-289 3 Conrad MT   453F ONVOY, LLC - MT 648   2022-12-09   
406-289 4 Conrad MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-289 6 Conrad MT   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-289 8 Conrad MT   453F ONVOY, LLC - MT 648   2012-12-17   
406-289 9 Conrad MT   453F ONVOY, LLC - MT 648   2012-12-17   

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

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