Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 815 [Rate centres in NPA 815] [Dial plan for NPA 815]

NXX: 635

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-635 A Chatsworth IL CHWOILXARS0  1015 FRONTIER NORTH, INC. - IL 366      
815-635 0 Chatsworth IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 366   2020-03-12   
815-635 1 Chatsworth IL   1015 FRONTIER NORTH, INC. - IL 366      
815-635 3 Chatsworth IL   1015 FRONTIER NORTH, INC. - IL 366      
815-635 4 Chatsworth IL   1015 FRONTIER NORTH, INC. - IL 366      
815-635 5 Chatsworth IL   846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366   2010-03-15   
815-635 6 Chatsworth IL   224C ONVOY, LLC 366   2019-01-17   
815-635 7 Chatsworth IL   508J CENTURYLINK COMMUNICATIONS, LLC 366   2014-08-12   
815-635 8 Chatsworth IL   224C ONVOY, LLC 366   2019-07-15   
815-635 9 Chatsworth IL   224C ONVOY, LLC 366   2019-07-15   

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

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