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: 479

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-479 A Castleton IL CSTNILXDRS0  1015 FRONTIER NORTH, INC. - IL 368      
309-479 0 Castleton IL PEORILPJDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 368   2015-11-01   
309-479 2 Castleton IL CSTNILXDRS0  1015 FRONTIER NORTH, INC. - IL 368      
309-479 4 Castleton IL KEWNILXDIMD  224C ONVOY, LLC 368   2020-06-15   
309-479 5 Castleton IL KEWNILXDFMD  624H ONVOY SPECTRUM, LLC 368   2023-07-08   
309-479 9 Castleton IL   145J TERRA NOVA TELECOM INC. 368   2025-06-06   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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