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: 337

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-337 A Cypress CA ANHMCA01XEY  516C AT&T CORP. 730      
657-337 0 Cypress CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-07-21   
657-337 1 Cypress CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2016-07-19   
657-337 2 Cypress CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2017-05-07   
657-337 3 Cypress CA   649C ONVOY, LLC - CA 730   2017-06-11   
657-337 4 Cypress CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2021-05-29   
657-337 5 Cypress CA   516C AT&T CORP. 730   2016-07-17   
657-337 6 Cypress CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2017-03-06   
657-337 7 Cypress CA   073H TELNYX LLC 730   2018-07-09   
657-337 8 Cypress CA   6529 T-MOBILE USA, INC. 730   2016-10-14   
657-337 9 Cypress CA   6529 T-MOBILE USA, INC. 730   2016-10-14   

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

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