Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 628 [Rate centres in NPA 628] [Dial plan for NPA 628]

NXX: 277

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-277 A San Rafael CA SNJUCACL3MD  073H TELNYX LLC 722      
628-277 0 San Rafael CA   073H TELNYX LLC 722   2021-03-22   
628-277 1 San Rafael CA   649C ONVOY, LLC - CA 722   2021-08-09   
628-277 2 San Rafael CA   624H ONVOY SPECTRUM, LLC 722   2021-07-23   
628-277 3 San Rafael CA   649C ONVOY, LLC - CA 722   2021-08-09   
628-277 4 San Rafael CA   649C ONVOY, LLC - CA 722   2021-08-09   
628-277 5 San Rafael CA   649C ONVOY, LLC - CA 722   2021-08-09   
628-277 6 San Rafael CA   939H COMMIO, LLC 722   2021-10-14   
628-277 7 San Rafael CA   965H FRACTEL, LLC 722   2021-08-02   
628-277 8 San Rafael CA   649C ONVOY, LLC - CA 722   2021-10-02   
628-277 9 San Rafael CA   649C ONVOY, LLC - CA 722   2021-10-02   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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