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.

Switch: MTPKCACG1MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
323-275 6 Los Angeles: DA 04 CA 776C CHARTER FIBERLINK CA-CCO, LLC - CA 730   2005-08-10   
323-344 6 Los Angeles: DA 03 CA 776C CHARTER FIBERLINK CA-CCO, LLC - CA 730   2005-08-10   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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