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: 783

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-783 A Yorba Linda CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2025-03-03   
657-783 7 Yorba Linda CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2025-03-03   
657-783 8 Yorba Linda CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2025-03-03   
657-783 9 Yorba Linda CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2025-03-03   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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