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: 252

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-252 A Mentone CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730      
840-252 0 Mentone CA   073H TELNYX LLC 730   2022-05-12   
840-252 1 Mentone CA   649C ONVOY, LLC - CA 730   2023-08-10   
840-252 2 Mentone CA   649C ONVOY, LLC - CA 730   2024-03-09   
840-252 3 Mentone CA   649C ONVOY, LLC - CA 730   2023-08-10   
840-252 4 Mentone CA   649C ONVOY, LLC - CA 730   2023-08-10   
840-252 5 Mentone CA   649C ONVOY, LLC - CA 730   2023-08-10   
840-252 6 Mentone CA   649C ONVOY, LLC - CA 730   2023-08-10   
840-252 7 Mentone CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2023-01-09   
840-252 8 Mentone CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2022-10-31   
840-252 9 Mentone CA   6529 T-MOBILE USA, INC. 730   2022-04-30   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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