Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 661 [Rate centres in NPA 661] [Dial plan for NPA 661]

NXX: 850

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-850 A Santa Clarita: Newhall-Castaic DA CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2026-07-23   
661-850 0 Santa Clarita: Newhall-Castaic DA CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2026-07-23   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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