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.

North Frannie, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-764 A BASNWYXCDS1  2296 TRI-COUNTY TEL. ASSN., INC. 654      
406-764 0   2296 TRI-COUNTY TEL. ASSN., INC. 654      
406-764 2   2296 TRI-COUNTY TEL. ASSN., INC. 654      
406-764 9   2296 TRI-COUNTY TEL. ASSN., INC. 654      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.