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: 738 [Rate centres in NPA 738] [Dial plan for NPA 738]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
738-666 A Montebello CA   649C ONVOY, LLC - CA 730   2026-02-17   
738-666 0 Montebello CA   649C ONVOY, LLC - CA 730   2026-02-17   
738-666 6 Montebello CA   649C ONVOY, LLC - CA 730   2026-02-17   

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

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.