Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Switch: HLNAMTMAWMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-204 8 Helena MT 5562 METROPCS, INC. 648   2017-08-31   
406-204 9 Helena MT 5562 METROPCS, INC. 648   2017-08-31   
406-310 1 Butte MT 6529 T-MOBILE USA, INC. 648   2024-07-07   
406-310 2 Butte MT 6529 T-MOBILE USA, INC. 648   2024-04-04   
406-310 6 Butte MT 6529 T-MOBILE USA, INC. 648   2021-02-07   
406-310 7 Butte MT 5562 METROPCS, INC. 648   2017-07-22   
406-310 8 Butte MT 5562 METROPCS, INC. 648   2017-07-22   
406-310 9 Butte MT 6529 T-MOBILE USA, INC. 648   2019-09-14   
406-410 3 Helena MT 6529 T-MOBILE USA, INC. 648   2021-06-04   
406-410 6 Helena MT 6529 T-MOBILE USA, INC. 648   2023-01-06   
406-410 7 Helena MT 6529 T-MOBILE USA, INC. 648   2023-01-06   
406-417 7 Helena MT 6529 T-MOBILE USA, INC. 648   2022-03-26   
406-440 5 Helena MT 6529 T-MOBILE USA, INC. 648   2024-02-22   
406-440 6 Helena MT 6529 T-MOBILE USA, INC. 648   2024-02-22   
406-475 6 Helena MT 6529 T-MOBILE USA, INC. 648   2024-09-27   
406-475 7 Helena MT 6529 T-MOBILE USA, INC. 648   2024-09-27   
406-479 0 Butte MT 6529 T-MOBILE USA, INC. 648   2022-01-02   
406-479 1 Butte MT 6529 T-MOBILE USA, INC. 648   2022-12-12   
406-479 9 Butte MT 6529 T-MOBILE USA, INC. 648   2022-08-08   
406-593 7 Butte MT 6529 T-MOBILE USA, INC. 648   2024-10-24   
406-593 8 Butte MT 6529 T-MOBILE USA, INC. 648   2024-12-26   
406-792 5 Butte MT 6529 T-MOBILE USA, INC. 648   2017-05-25   
406-792 6 Butte MT 6529 T-MOBILE USA, INC. 648   2017-05-25   
406-916 A Helena MT 6529 T-MOBILE USA, INC. 648      
406-916 1 Helena MT 6529 T-MOBILE USA, INC. 648   2022-08-27   
406-916 2 Helena MT 6529 T-MOBILE USA, INC. 648   2021-03-12   
406-916 6 Helena MT 6529 T-MOBILE USA, INC. 648   2020-07-30   
406-916 7 Helena MT 6529 T-MOBILE USA, INC. 648   2019-03-18   
406-916 8 Helena MT 6529 T-MOBILE USA, INC. 648   2017-05-25   
406-916 9 Helena MT 6529 T-MOBILE USA, INC. 648   2017-05-25   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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