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: 831 [Rate centres in NPA 831] [Dial plan for NPA 831]

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-604 A Ben Lomond CA OKLDCAAN4KD  7379 MATRIX TELECOM, LLC. SII TNCI - CA 722      

Last updated: Sun, 29 Nov 2020 13:13:58 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.