Local Calling Guide

Area code/prefix search

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Northbrook, IL

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
847-974 A LBRDILGOAMD  6630 SPOK, INC. 358      
847-992 A CHCGILBWCM2  9748 AMERICAN MESSAGING SERVICES, LLC 358      

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Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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