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: 258

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-258 A Nicasio CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722      
628-258 0 Nicasio CA   649C ONVOY, LLC - CA 722   2017-12-17   
628-258 1 Nicasio CA   073H TELNYX LLC 722   2018-05-11   
628-258 2 Nicasio CA   707H INTEGRATED PATH COMMUNICATIONS, LLC - CA 722   2018-07-13   
628-258 3 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2019-03-22   
628-258 4 Nicasio CA   515J IP HORIZON LLC 722   2021-05-01   
628-258 5 Nicasio CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2018-08-31   
628-258 6 Nicasio CA   649C ONVOY, LLC - CA 722   2019-07-28   
628-258 7 Nicasio CA   649C ONVOY, LLC - CA 722   2019-07-28   
628-258 8 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2018-04-30   
628-258 9 Nicasio CA   6529 T-MOBILE USA, INC. 722   2017-12-16   

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

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