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: 508

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-508 A Cypress CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
657-508 0 Cypress CA   649C ONVOY, LLC - CA 730   2021-09-03   
657-508 1 Cypress CA   649C ONVOY, LLC - CA 730   2021-09-03   
657-508 2 Cypress CA   649C ONVOY, LLC - CA 730   2021-09-03   
657-508 3 Cypress CA   649C ONVOY, LLC - CA 730   2021-09-03   
657-508 5 Cypress CA   939H COMMIO, LLC 730   2021-10-21   
657-508 6 Cypress CA   939H COMMIO, LLC 730   2021-10-21   
657-508 7 Cypress CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2021-09-24   
657-508 8 Cypress CA   6529 T-MOBILE USA, INC. 730   2021-09-02   
657-508 9 Cypress CA   6529 T-MOBILE USA, INC. 730   2021-09-02   

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

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