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.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: BLNGMTWE8MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
307-227 A Mammoth WY 7575 CENTURYLINK COMMUNICATIONS LLC 650      
406-729 A Wilsall MT 7575 CENTURYLINK COMMUNICATIONS LLC 650      
406-970 A Billings MT 7575 CENTURYLINK COMMUNICATIONS LLC 650      

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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