Local Calling Guide

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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 387

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-387 A Yorba Linda CA LSANCARCD3S  649C ONVOY, LLC - CA 730      
657-387 0 Yorba Linda CA   649C ONVOY, LLC - CA 730   2016-03-21   
657-387 1 Yorba Linda CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2016-06-09   
657-387 2 Yorba Linda CA   649C ONVOY, LLC - CA 730   2016-07-18   
657-387 3 Yorba Linda CA   321J HD CARRIER LLC 730   2016-06-11   
657-387 4 Yorba Linda CA   321J HD CARRIER LLC 730   2016-06-11   
657-387 5 Yorba Linda CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-08-20   
657-387 6 Yorba Linda CA   321J HD CARRIER LLC 730   2016-09-01   
657-387 7 Yorba Linda CA   649C ONVOY, LLC - CA 730   2016-03-22   
657-387 8 Yorba Linda CA   649C ONVOY, LLC - CA 730   2016-03-22   
657-387 9 Yorba Linda CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-07-30   

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

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