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: 723

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-723 A Colfax IL CLFXILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-723 1 Colfax IL   846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366   2010-03-15   
309-723 2 Colfax IL   1015 FRONTIER NORTH, INC. - IL 366      
309-723 3 Colfax IL   1015 FRONTIER NORTH, INC. - IL 366      
309-723 4 Colfax IL   1015 FRONTIER NORTH, INC. - IL 366      
309-723 5 Colfax IL   1015 FRONTIER NORTH, INC. - IL 366      
309-723 6 Colfax IL   1015 FRONTIER NORTH, INC. - IL 366      
309-723 7 Colfax IL   224C ONVOY, LLC 366   2019-01-17   
309-723 8 Colfax IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 366   2004-07-16   
309-723 9 Colfax IL   508J CENTURYLINK COMMUNICATIONS, LLC 366   2014-08-12   

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

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