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: 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 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: Thu, 16 Jul 2026 02:21:55 UTC

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