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: 330

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-330 A Clinton MT   792K CHARTER IP ENABLED SERVICES, LLC 648      
406-330 0 Clinton MT   6529 T-MOBILE USA, INC. 648      
406-330 2 Clinton MT   792K CHARTER IP ENABLED SERVICES, LLC 648      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.