Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Fillmore, IL

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
217-538 A FLMRILXCRS0  1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 976      
447-214 A TYVLIL35DS0  197H COMPUTER TECHNIQUES, INC. - IL 976      

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

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