Local Calling Guide

Area code/prefix search

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Massbach, IL

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
815-598 A MSBCILXARS0  1036 FRONTIER NORTH, INC. - IL 360      
815-598 0   624H ONVOY SPECTRUM, LLC 360   2024-10-31   
815-598 3   1036 FRONTIER NORTH, INC. - IL 360      
815-598 4   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 360   2022-04-17   
815-598 5   224C ONVOY, LLC 360   2020-07-18   
815-598 7   508J CENTURYLINK COMMUNICATIONS, LLC 360   2016-02-18   
815-598 8   224C ONVOY, LLC 360   2021-04-02   
815-598 9   1036 FRONTIER NORTH, INC. - IL 360      
815-898 A FRPTILBUDS0  443F AERO NORTH COMMUNICATIONS, INC. - IL 360      

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

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