Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 618 [Rate centres in NPA 618] [Dial plan for NPA 618]

NXX: 566

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
618-566 A Mascoutah IL MSCTILXEDS0  1036 FRONTIER NORTH, INC. - IL 520      
618-566 0 Mascoutah IL   792K CHARTER IP ENABLED SERVICES, LLC 520   2005-09-25   
618-566 1 Mascoutah IL   224C ONVOY, LLC 520   2023-09-18   
618-566 2 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 3 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 4 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 5 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 6 Mascoutah IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 520   2005-03-10   
618-566 7 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 8 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      
618-566 9 Mascoutah IL   1036 FRONTIER NORTH, INC. - IL 520      

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

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