Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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 SNMNCAXPX3Z  649C ONVOY, LLC - CA 730   2025-10-25   
661-683 0 Lancaster CA SNMNCAXPX3Z  649C ONVOY, LLC - CA 730   2025-10-25   
661-683 1 Lancaster CA LSANCAJWMMD  490J BOOST SUBSCRIBERCO L.L.C. 730   2025-10-27   
661-683 8 Lancaster CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-11-14   
661-683 9 Lancaster CA SNMNCAXPX3Z  649C ONVOY, LLC - CA 730   2025-11-09   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.