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: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-237 A Ontario CA ONTRCAXPXPY  649C ONVOY, LLC - CA 730   2024-01-23   
840-237 0 Ontario CA   939H COMMIO, LLC 730   2024-01-28   
840-237 1 Ontario CA   939H COMMIO, LLC 730   2024-01-28   
840-237 2 Ontario CA   649C ONVOY, LLC - CA 730   2023-11-20   
840-237 3 Ontario CA   649C ONVOY, LLC - CA 730   2023-11-20   
840-237 4 Ontario CA   649C ONVOY, LLC - CA 730   2023-11-20   
840-237 5 Ontario CA   649C ONVOY, LLC - CA 730   2023-11-21   
840-237 6 Ontario CA   7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730   2024-05-06   
840-237 7 Ontario CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2024-11-15   
840-237 8 Ontario CA   649C ONVOY, LLC - CA 730   2024-07-05   
840-237 9 Ontario CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2024-11-27   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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