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: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-320 A San Francisco: Montrose-Evergreen DA CA SNFCCA21XNZ  624H ONVOY SPECTRUM, LLC 722   2025-03-21   
628-320 0 San Francisco: Montrose-Evergreen DA CA SNFCCA21XNZ  624H ONVOY SPECTRUM, LLC 722   2025-03-21   
628-320 1 San Francisco: Montrose-Evergreen DA CA   649C ONVOY, LLC - CA 722   2026-08-23   
628-320 8 San Francisco: Montrose-Evergreen DA CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2026-09-19   
628-320 9 San Francisco: Montrose-Evergreen DA CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2026-09-19   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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