Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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OCN: 385L SEQUOIA WIRELESS, LLC

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
510-310 A Hayward CA   722   2026-04-19   
510-310 0 Hayward CA   722   2026-04-19   
510-310 1 Hayward CA   722   2026-04-19   
510-310 5 Hayward CA   722   2026-04-19   
510-310 9 Hayward CA   722   2026-04-19   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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