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: 644

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-644 A Cypress CA LSANCAJWIMD  965H FRACTEL, LLC 730      
657-644 0 Cypress CA   073H TELNYX LLC 730   2021-02-26   
657-644 1 Cypress CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2021-04-22   
657-644 2 Cypress CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2021-06-21   
657-644 3 Cypress CA   649C ONVOY, LLC - CA 730   2021-07-22   
657-644 4 Cypress CA   965H FRACTEL, LLC 730   2020-11-15   
657-644 5 Cypress CA   649C ONVOY, LLC - CA 730   2020-11-25   
657-644 6 Cypress CA   649C ONVOY, LLC - CA 730   2020-11-25   
657-644 7 Cypress CA   649C ONVOY, LLC - CA 730   2020-11-25   
657-644 8 Cypress CA   649C ONVOY, LLC - CA 730   2020-11-25   
657-644 9 Cypress CA   649C ONVOY, LLC - CA 730   2021-07-22   

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

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