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: 204

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-204 A Nicasio CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722      
628-204 0 Nicasio CA   515J IP HORIZON LLC 722   2016-09-11   
628-204 1 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2016-10-10   
628-204 2 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2016-10-10   
628-204 3 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2016-10-10   
628-204 4 Nicasio CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2016-10-10   
628-204 5 Nicasio CA   649C ONVOY, LLC - CA 722   2016-10-30   
628-204 6 Nicasio CA   649C ONVOY, LLC - CA 722   2016-10-30   
628-204 7 Nicasio CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2016-12-08   
628-204 8 Nicasio CA   649C ONVOY, LLC - CA 722   2016-10-14   
628-204 9 Nicasio CA   6529 T-MOBILE USA, INC. 722   2016-08-22   

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

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