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: 287

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-287 A Marshall CA   649C ONVOY, LLC - CA 730   2026-02-02   
840-287 0 Marshall CA   649C ONVOY, LLC - CA 730   2026-02-02   
840-287 1 Marshall CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2026-02-20   
840-287 2 Marshall CA   649C ONVOY, LLC - CA 730   2026-03-14   
840-287 6 Marshall CA   073H TELNYX LLC 730   2026-05-03   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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