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: 224 [Rate centres in NPA 224] [Dial plan for NPA 224]

NXX: 540

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
224-540 A Round Lake IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
224-540 0 Round Lake IL   224C ONVOY, LLC 358   2016-03-04   
224-540 1 Round Lake IL   224C ONVOY, LLC 358   2016-03-04   
224-540 2 Round Lake IL   073H TELNYX LLC 358   2017-04-24   
224-540 3 Round Lake IL   6529 T-MOBILE USA, INC. 358   2017-02-18   
224-540 4 Round Lake IL   6529 T-MOBILE USA, INC. 358   2017-02-18   
224-540 5 Round Lake IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
224-540 6 Round Lake IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
224-540 7 Round Lake IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
224-540 8 Round Lake IL   515J IP HORIZON LLC 358   2016-08-09   
224-540 9 Round Lake IL   6529 T-MOBILE USA, INC. 358   2015-12-21   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.