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: 529

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-529 A El Segundo CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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