Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 779 [Rate centres in NPA 779] [Dial plan for NPA 779]

NXX: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
779-431 A De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-10-03   
779-431 0 De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-10-29   
779-431 1 De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-11-14   
779-431 6 De Kalb IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 364   2025-12-24   
779-431 7 De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-11-14   
779-431 8 De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-11-14   
779-431 9 De Kalb IL   6529 T-MOBILE USA, INC. 364   2025-10-03   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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