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: 291

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-291 A Mill Valley CA CNCRCADOCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 722      
628-291 0 Mill Valley CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2024-11-10   
628-291 1 Mill Valley CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2024-11-10   
628-291 2 Mill Valley CA   624H ONVOY SPECTRUM, LLC 722   2025-01-30   
628-291 3 Mill Valley CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2025-06-14   
628-291 8 Mill Valley CA SNJUCACLDS1  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2024-11-19   
628-291 9 Mill Valley CA CNCRCADOCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2023-09-18   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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