Local Calling Guide

Area code/prefix search

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NPA: 628 [Rate centres in NPA 628] [Dial plan for NPA 628]

NXX: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-256 A San Francisco: Montrose-Evergreen DA CA SNRTCAHFDS0  433E SONIC TELECOM, LLC - CA 722      
628-256 0 San Francisco: Montrose-Evergreen DA CA SNRTCAHFDS0  433E SONIC TELECOM, LLC - CA 722   2016-12-01   
628-256 1 San Francisco: Montrose-Evergreen DA CA SNRTCAHFDS0  433E SONIC TELECOM, LLC - CA 722   2016-12-01   
628-256 2 San Francisco: Montrose-Evergreen DA CA SNRTCAHFDS0  433E SONIC TELECOM, LLC - CA 722   2017-02-03   
628-256 3 San Francisco: Montrose-Evergreen DA CA SNRTCAHFDS0  433E SONIC TELECOM, LLC - CA 722   2017-02-03   
628-256 4 San Francisco: Montrose-Evergreen DA CA SNJUCACL3MD  073H TELNYX LLC 722   2017-03-23   
628-256 5 San Francisco: Montrose-Evergreen DA CA HYWRCAMCDMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2017-02-16   
628-256 6 San Francisco: Montrose-Evergreen DA CA   829J PAETEC ITEL, LLC 722   2017-03-09   
628-256 7 San Francisco: Montrose-Evergreen DA CA SNJUCACLDS1  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2017-07-09   
628-256 8 San Francisco: Montrose-Evergreen DA CA HYWRCAMCDMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2017-12-20   

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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