Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 310 [Rate centres in NPA 310] [Dial plan for NPA 310]

NXX: 458

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-458 A Santa Monica: Santa Monica DA CA SNMNCAXGDS0  2319 FRONTIER CALIFORNIA INC. 730      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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