Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Willow Hill, IL

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
618-455 A WWHLILXERS0  1015 FRONTIER NORTH, INC. - IL 978      
618-455 0   9915 DELTA COMMS, LLC DBA CLEARWAVE COMMUNICATIONS - IL 978   2003-06-04   
618-455 1   224C ONVOY, LLC 978   2023-10-08   
618-455 2   624H ONVOY SPECTRUM, LLC 978   2023-07-29   
618-455 3   1015 FRONTIER NORTH, INC. - IL 978      
618-455 5   224C ONVOY, LLC 978   2021-04-09   
618-455 8   224C ONVOY, LLC 978   2020-03-13   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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