Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 350 [Rate centres in NPA 350] [Dial plan for NPA 350]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
350-257 A Ripon CA   6010 NEW CINGULAR WIRELESS PCS, LLC 738   2026-06-19   
350-257 0 Ripon CA   649C ONVOY, LLC - CA 738   2026-06-22   
350-257 9 Ripon CA   6010 NEW CINGULAR WIRELESS PCS, LLC 738   2026-06-19   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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