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: WTSNILXCDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
217-536 A Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 0 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 1 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 5 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 6 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 8 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
217-536 9 Watson IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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