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: 840 [Rate centres in NPA 840] [Dial plan for NPA 840]

NXX: 285

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-285 A Fontana CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2025-11-10   
840-285 0 Fontana CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2025-11-10   
840-285 1 Fontana CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2025-11-11   
840-285 2 Fontana CA LSANCAJWDS9  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2026-07-16   
840-285 3 Fontana CA   649C ONVOY, LLC - CA 730   2026-08-30   
840-285 4 Fontana CA   649C ONVOY, LLC - CA 730   2026-08-30   
840-285 5 Fontana CA   649C ONVOY, LLC - CA 730   2026-09-12   
840-285 8 Fontana CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-07-17   
840-285 9 Fontana CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-05-17   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.