Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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 0 Yorba Linda CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-01   
657-783 1 Yorba Linda CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-01   
657-783 2 Yorba Linda CA   321J HD CARRIER LLC 730   2026-05-15   
657-783 3 Yorba Linda CA   321J HD CARRIER LLC 730   2026-05-15   
657-783 4 Yorba Linda CA   321J HD CARRIER LLC 730   2026-05-15   
657-783 5 Yorba Linda CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-01   
657-783 6 Yorba Linda CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2026-06-01   
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: Tue, 16 Jun 2026 00:09:45 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.