Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: SPVYILXARS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
815-663 A Spring Valley IL 1015 FRONTIER NORTH, INC. - IL 368      
815-664 A Spring Valley IL 1015 FRONTIER NORTH, INC. - IL 368      

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

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