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: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-837 A Pomona CA LSANCAJWJMD  516J TON80 COMMUNICATIONS, LLC 730      
840-837 0 Pomona CA   6529 T-MOBILE USA, INC. 730   2022-05-20   
840-837 1 Pomona CA   649C ONVOY, LLC - CA 730   2023-01-31   
840-837 2 Pomona CA   649C ONVOY, LLC - CA 730   2023-01-31   
840-837 3 Pomona CA   624H ONVOY SPECTRUM, LLC 730   2022-03-12   
840-837 4 Pomona CA   516J TON80 COMMUNICATIONS, LLC 730   2022-03-11   
840-837 5 Pomona CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-10-09   
840-837 6 Pomona CA   6529 T-MOBILE USA, INC. 730   2022-03-12   
840-837 7 Pomona CA   6529 T-MOBILE USA, INC. 730   2022-03-12   
840-837 8 Pomona CA   624H ONVOY SPECTRUM, LLC 730   2022-03-12   
840-837 9 Pomona CA   073H TELNYX LLC 730   2022-03-12   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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