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: 572

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-572 A Fremont-Newark: Oliver DA CA HYWRCAMCDS0  7240 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA 722      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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