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: 388

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
779-388 A Crystal Lake IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2024-05-25   
779-388 0 Crystal Lake IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2024-05-25   
779-388 1 Crystal Lake IL   6529 T-MOBILE USA, INC. 358   2025-02-06   
779-388 3 Crystal Lake IL   145J TERRA NOVA TELECOM INC. 358   2025-10-06   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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