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: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-240 A Diamond Bar CA COVNCAXFX3Y  649C ONVOY, LLC - CA 730      
840-240 0 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-10-30   
840-240 1 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-01-23   
840-240 2 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-01-23   
840-240 3 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-01-23   
840-240 4 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-01-23   
840-240 5 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-03-02   
840-240 6 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-03-02   
840-240 7 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-03-02   
840-240 8 Diamond Bar CA   649C ONVOY, LLC - CA 730   2023-03-02   
840-240 9 Diamond Bar CA   6529 T-MOBILE USA, INC. 730   2023-09-22   

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

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