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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-310 A Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 0 Belvedere CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2025-06-21   
628-310 4 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 5 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 6 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 7 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 8 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   
628-310 9 Belvedere CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722   2024-06-07   

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

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