Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: CHCGILMHRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
773-646 A Chicago Zone 09-Mitchell IL 9329 ILLINOIS BELL TEL CO 358      

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

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