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: 683

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-683 A Lancaster CA   649C ONVOY, LLC - CA 730   2025-10-25   
661-683 0 Lancaster CA   649C ONVOY, LLC - CA 730   2025-10-25   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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