Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 510 [Rate centres in NPA 510] [Dial plan for NPA 510]

NXX: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-310 A Hayward CA   385L SEQUOIA WIRELESS, LLC 722   2026-04-19   
510-310 0 Hayward CA   385L SEQUOIA WIRELESS, LLC 722   2026-04-19   
510-310 1 Hayward CA   385L SEQUOIA WIRELESS, LLC 722   2026-04-19   
510-310 5 Hayward CA   385L SEQUOIA WIRELESS, LLC 722   2026-04-19   
510-310 8 Hayward CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2026-08-17   
510-310 9 Hayward CA   385L SEQUOIA WIRELESS, LLC 722   2026-04-19   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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