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: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-503 A Billings MT BLNGMTWELMD  318J COMCAST IP PHONE, LLC 650      
406-503 0 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2023-08-20   
406-503 1 Billings MT BLNGMTWELMD  318J COMCAST IP PHONE, LLC 650   2023-06-04   
406-503 2 Billings MT BLNGMTMAXMD  6529 T-MOBILE USA, INC. 650   2024-01-26   
406-503 3 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2024-02-09   
406-503 4 Billings MT BLNGMTMAXMD  5562 METROPCS, INC. 650   2023-09-24   
406-503 5 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2024-02-09   
406-503 6 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2024-02-09   
406-503 7 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2024-02-09   
406-503 8 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2023-08-20   
406-503 9 Billings MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2023-08-20   

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

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