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: 506

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-506 A Billings MT BLNGMT93BMD  321J HD CARRIER LLC 650      
406-506 0 Billings MT BLNGMT93BMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2022-10-07   
406-506 1 Billings MT BLNGMT93BMD  321J HD CARRIER LLC 650   2020-11-01   
406-506 2 Billings MT BLNGMT93BMD  321J HD CARRIER LLC 650   2020-11-01   
406-506 3 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-506 4 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2020-10-05   
406-506 5 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2020-10-05   
406-506 6 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2020-10-05   
406-506 7 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-506 8 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2020-09-03   
406-506 9 Billings MT BLNGMT93BMD  321J HD CARRIER LLC 650   2020-07-23   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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