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: 379

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-379 A Stanford IL STFRILXDRS0  1015 FRONTIER NORTH, INC. - IL 366      
309-379 0 Stanford IL   846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366   2010-03-15   
309-379 1 Stanford IL   224C ONVOY, LLC 366   2021-08-12   
309-379 2 Stanford IL   1015 FRONTIER NORTH, INC. - IL 366      
309-379 3 Stanford IL   1015 FRONTIER NORTH, INC. - IL 366      
309-379 4 Stanford IL   1015 FRONTIER NORTH, INC. - IL 366      
309-379 5 Stanford IL   224C ONVOY, LLC 366   2021-07-04   
309-379 7 Stanford IL   508J CENTURYLINK COMMUNICATIONS, LLC 366   2014-08-13   
309-379 8 Stanford IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 366   2004-07-17   
309-379 9 Stanford IL   224C ONVOY, LLC 366   2021-04-03   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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