Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: RMSYILXEDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
618-423 A Ramsey IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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