Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 773 [Rate centres in NPA 773] [Dial plan for NPA 773]

NXX: 276

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
773-276 A Chicago Zone 04-Humboldt IL CHCGILHBDS1  9329 ILLINOIS BELL TEL CO 358      

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

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