Local Calling Guide

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NPA: 840 [Rate centres in NPA 840] [Dial plan for NPA 840]

NXX: 588

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-588 A Diamond Bar CA LSANCAJWIMD  965H FRACTEL, LLC 730      
840-588 0 Diamond Bar CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-01-21   
840-588 1 Diamond Bar CA LSANCA543MD  073H TELNYX LLC 730   2022-06-16   
840-588 2 Diamond Bar CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2022-08-25   
840-588 3 Diamond Bar CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-07-29   
840-588 4 Diamond Bar CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-07-29   
840-588 5 Diamond Bar CA RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2021-12-28   
840-588 6 Diamond Bar CA RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2021-12-28   
840-588 7 Diamond Bar CA RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2021-12-28   
840-588 8 Diamond Bar CA LSANCAJWIMD  965H FRACTEL, LLC 730   2021-12-27   
840-588 9 Diamond Bar CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2022-03-11   

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

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