Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 390

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-390 A Orange CA LSANCARCD3S  649C ONVOY, LLC - CA 730      
657-390 0 Orange CA   649C ONVOY, LLC - CA 730   2016-03-31   
657-390 1 Orange CA   649C ONVOY, LLC - CA 730   2016-03-31   
657-390 2 Orange CA   321J HD CARRIER LLC 730   2016-06-04   
657-390 3 Orange CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2016-05-06   
657-390 4 Orange CA   321J HD CARRIER LLC 730   2016-06-04   
657-390 5 Orange CA   649C ONVOY, LLC - CA 730   2017-11-16   
657-390 6 Orange CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2016-08-22   
657-390 7 Orange CA   321J HD CARRIER LLC 730   2016-06-04   
657-390 8 Orange CA   321J HD CARRIER LLC 730   2016-06-04   
657-390 9 Orange CA   649C ONVOY, LLC - CA 730   2017-12-06   

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

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