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.

Harlowton, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-632 A WSSPMTXCDS0  3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 1   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 2   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 3   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 4   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 5   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 6   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 7   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      
406-632 8   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2019-01-11   
406-632 9   3310 TRIANGLE TEL. COOP. ASSN., INC. 650      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.