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.

NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-428 A Grass Range MT GRRNMTXCRS1  2246 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-428 2 Grass Range MT   2246 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      
406-428 8 Grass Range MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-12-17   

Last updated: Thu, 10 Sep 2020 02:15:24 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.