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: 285

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-285 A Fontana CA   649C ONVOY, LLC - CA 730   2025-11-10   
840-285 0 Fontana CA   649C ONVOY, LLC - CA 730   2025-11-10   
840-285 1 Fontana CA   649C ONVOY, LLC - CA 730   2025-11-11   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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