Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 357 [Rate centres in NPA 357] [Dial plan for NPA 357]

NXX: 357

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
357-357 A Springville CA   649C ONVOY, LLC - CA 728   2026-12-06   
357-357 3 Springville CA   649C ONVOY, LLC - CA 728   2026-12-06   
357-357 7 Springville CA   649C ONVOY, LLC - CA 728   2026-12-06   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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