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: 275

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-275 A Pomona CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-05-02   
840-275 0 Pomona CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-05-02   
840-275 1 Pomona CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-05-02   
840-275 3 Pomona CA   490J BOOST SUBSCRIBERCO L.L.C. 730   2025-08-09   
840-275 5 Pomona CA   490J BOOST SUBSCRIBERCO L.L.C. 730   2025-11-06   
840-275 7 Pomona CA   490J BOOST SUBSCRIBERCO L.L.C. 730   2026-01-05   
840-275 8 Pomona CA   649C ONVOY, LLC - CA 730   2026-04-05   
840-275 9 Pomona CA   649C ONVOY, LLC - CA 730   2026-04-05   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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