Local Calling Guide

Area code/prefix search

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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 1 Plainfield IL   624H ONVOY SPECTRUM, LLC 358   2026-08-28   
779-436 2 Plainfield IL   624H ONVOY SPECTRUM, LLC 358   2026-08-28   
779-436 9 Plainfield IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2026-01-09   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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