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: CHCGILCLDS9

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
312-239 A Chicago Zone 01-Canal IL 7421 AT&T - LOCAL 358      
312-239 4 Chicago Zone 01-Canal IL 7421 AT&T - LOCAL 358      
312-239 5 Chicago Zone 01-Canal IL 7421 AT&T - LOCAL 358      
312-239 9 Chicago Zone 01-Canal IL 7421 AT&T - LOCAL 358      
773-952 5 Chicago Zone 07-Stewart IL 7421 AT&T - LOCAL 358   2007-08-05   

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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