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: 933

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-933 A Fremont-Newark: Oliver DA CA SNJSCAYB0MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 722      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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