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: 779 [Rate centres in NPA 779] [Dial plan for NPA 779]

NXX: 436

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
779-436 A Plainfield IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2026-01-09   
779-436 0 Plainfield IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2026-07-23   
779-436 9 Plainfield IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2026-01-09   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.