Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 224 [Rate centres in NPA 224] [Dial plan for NPA 224]

NXX: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
224-320 A Lake Zurich IL CHCGILWUX6X  460K FIRST COMMUNICATIONS, LLC 358      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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