Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 840 [Rate centres in NPA 840] [Dial plan for NPA 840]

NXX: 279

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-279 A Ontario CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-12   
840-279 0 Ontario CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-12   
840-279 1 Ontario CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-12   
840-279 2 Ontario CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-12   
840-279 3 Ontario CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2026-11-06   
840-279 4 Ontario CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-04-23   
840-279 5 Ontario CA   649C ONVOY, LLC - CA 730   2026-08-31   
840-279 6 Ontario CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2026-11-06   
840-279 7 Ontario CA   649C ONVOY, LLC - CA 730   2026-08-17   
840-279 8 Ontario CA   649C ONVOY, LLC - CA 730   2026-08-17   
840-279 9 Ontario CA   649C ONVOY, LLC - CA 730   2026-08-17   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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