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: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-600 A Colton CA LSANCAJWIMD  965H FRACTEL, LLC 730      
840-600 0 Colton CA LSANCAJWIMD  965H FRACTEL, LLC 730   2021-03-06   
840-600 1 Colton CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2021-03-18   
840-600 2 Colton CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2021-03-18   
840-600 3 Colton CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2021-07-30   
840-600 4 Colton CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2021-07-30   
840-600 5 Colton CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2021-07-30   
840-600 6 Colton CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2021-07-30   
840-600 7 Colton CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2021-09-12   
840-600 8 Colton CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2021-09-12   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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