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: CHCGILIRDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
773-267 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-279 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-463 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-478 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-509 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-539 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-583 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-588 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-604 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-730 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-866 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      
773-961 A Chicago Zone 02-Irving IL 9329 AMERITECH ILLINOIS 358      

Last updated: Sun, 10 Nov 2019 13:49:34 UTC

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