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: 225

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-225 A Boulder MT BLDRMTMARS1  9636 QWEST CORPORATION 648      
406-225 0 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-10   
406-225 1 Boulder MT GRFLMTMAKMD  624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-225 2 Boulder MT HLNAMTMANMD  357E YMAX COMMUNICATIONS CORP. - MT 648   2009-09-30   
406-225 3 Boulder MT BLDRMTMARS1  9636 QWEST CORPORATION 648      
406-225 4 Boulder MT BLDRMTMARS1  9636 QWEST CORPORATION 648      
406-225 5 Boulder MT HLNAMTMANMD  357E YMAX COMMUNICATIONS CORP. - MT 648   2009-02-17   
406-225 6 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2022-10-29   
406-225 7 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2007-03-19   
406-225 8 Boulder MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2022-10-29   
406-225 9 Boulder MT BLDRMTMARS1  9636 QWEST CORPORATION 648      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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