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: 341

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-341 A Brea CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
657-341 0 Brea CA   649C ONVOY, LLC - CA 730   2016-08-28   
657-341 1 Brea CA   649C ONVOY, LLC - CA 730   2016-08-28   
657-341 2 Brea CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-09   
657-341 3 Brea CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-09   
657-341 4 Brea CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-09   
657-341 5 Brea CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-09   
657-341 6 Brea CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2016-11-07   
657-341 7 Brea CA   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 730   2017-03-12   
657-341 8 Brea CA   6529 T-MOBILE USA, INC. 730   2016-08-27   
657-341 9 Brea CA   6529 T-MOBILE USA, INC. 730   2016-08-27   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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