Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 378

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-378 A Downs IL DWNSILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-378 0 Downs IL BLTNILXDXPX  846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366   2010-03-15   
309-378 1 Downs IL DWNSILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-378 2 Downs IL DWNSILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-378 3 Downs IL DWNSILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-378 4 Downs IL DWNSILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-378 5 Downs IL BLTNILTS7MD  145J TERRA NOVA TELECOM INC. 366   2022-11-02   
309-378 6 Downs IL BLTNILXDXHY  624H ONVOY SPECTRUM, LLC 366   2023-06-02   
309-378 8 Downs IL BLTNILATVMD  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 366   2004-07-16   
309-378 9 Downs IL BLTNILTSYMD  495J STRATUS NETWORKS 366   2020-10-14   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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