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: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-273 A Mentone CA   649C ONVOY, LLC - CA 730   2025-03-29   
840-273 0 Mentone CA   649C ONVOY, LLC - CA 730   2025-03-29   
840-273 1 Mentone CA   649C ONVOY, LLC - CA 730   2025-10-13   
840-273 2 Mentone CA   516C AT&T CORP. 730   2026-01-06   
840-273 8 Mentone CA   649C ONVOY, LLC - CA 730   2026-01-05   
840-273 9 Mentone CA   649C ONVOY, LLC - CA 730   2025-11-28   

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

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