Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 858 [Rate centres in NPA 858] [Dial plan for NPA 858]

NXX: 728

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-728 A San Diego: Mira Mesa DA CA SNDGCA0250Z  6630 USA MOBILITY WIRELESS, INC. 732      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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