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: 477

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-477 A Mill Valley CA SNJUCACL7MD  965H FRACTEL, LLC 722      
628-477 0 Mill Valley CA SNFCCAMKX6Y  515J IP HORIZON LLC 722   2021-05-01   
628-477 1 Mill Valley CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2021-08-09   
628-477 2 Mill Valley CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2021-08-09   
628-477 3 Mill Valley CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2021-08-09   
628-477 4 Mill Valley CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2021-08-09   
628-477 5 Mill Valley CA   829J PAETEC ITEL, LLC 722   2021-07-16   
628-477 7 Mill Valley CA SNJUCACL7MD  965H FRACTEL, LLC 722   2021-04-09   
628-477 8 Mill Valley CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2023-08-11   
628-477 9 Mill Valley CA CNCRCADOCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2021-11-08   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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