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: 820 [Rate centres in NPA 820] [Dial plan for NPA 820]

NXX: 242

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
820-242 A El Rio CA   649C ONVOY, LLC - CA 730   2025-11-09   
820-242 0 El Rio CA   649C ONVOY, LLC - CA 730   2025-11-09   
820-242 1 El Rio CA   516C AT&T CORP. 730   2026-01-06   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.