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: BLNGMTMAX6X

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-325 A Billings MT 732J NUSO, LLC 650      
406-325 1 Billings MT 732J NUSO, LLC 650   2022-09-29   

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

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