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-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
312-210 A Chicago Zone 01-Calumet IL CHCGILCNDS5  358      
312-210 1 Chicago Zone 01-Calumet IL   358   2018-09-09   
312-686 A Chicago Zone 01-Calumet IL CHCGILCNGMD  358      
312-686 1 Chicago Zone 01-Calumet IL   358   2017-01-27   
773-516 A Chicago Zone 02-Edgewater IL CHCGILCNDS5  358      
773-516 8 Chicago Zone 02-Edgewater IL   358   2018-09-06   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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