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: 840

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-840 A Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   
840-840 4 Ontario CA   516C AT&T CORP. 730   2026-01-06   
840-840 5 Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   
840-840 6 Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   
840-840 7 Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   
840-840 8 Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   
840-840 9 Ontario CA   624H ONVOY SPECTRUM, LLC 730   2025-11-11   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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