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: 997

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-997 A Claremont-San Dimas CA   649C ONVOY, LLC - CA 730   2026-06-27   
840-997 0 Claremont-San Dimas CA   649C ONVOY, LLC - CA 730   2026-06-27   
840-997 1 Claremont-San Dimas CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2026-06-29   
840-997 2 Claremont-San Dimas CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2026-06-29   
840-997 8 Claremont-San Dimas CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-29   
840-997 9 Claremont-San Dimas CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-29   

Last updated: Fri, 10 Jul 2026 02:55:48 UTC

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