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: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-221 A Butte MT HLNAMTMAKMD  7421 AT&T - LOCAL 648      
406-221 0 Butte MT   073H TELNYX LLC 648   2024-02-16   
406-221 1 Butte MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-13   
406-221 2 Butte MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-13   
406-221 3 Butte MT HLNAMTMAMMD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 648   2007-05-16   
406-221 4 Butte MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-13   
406-221 5 Butte MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2012-12-13   
406-221 6 Butte MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2010-11-05   
406-221 7 Butte MT HLNAMTHHPS1  008E BRESNAN BROADBAND OF MONTANA, LLC - MT [CHARTER] 648   2008-08-09   
406-221 8 Butte MT GRFLMTMAHMD  073H TELNYX LLC 648   2020-08-07   
406-221 9 Butte MT HLNAMTMAKMD  7421 AT&T - LOCAL 648      

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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