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: 356

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-356 A Henry IL PEORILTCDS0  5800 ITV-3, LLC D/B/A I3 BROADBAND 368      
309-356 1 Henry IL   846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 368   2010-03-15   
309-356 3 Henry IL   224C ONVOY, LLC 368   2018-08-02   
309-356 4 Henry IL   224C ONVOY, LLC 368   2021-04-03   
309-356 5 Henry IL   145J TERRA NOVA TELECOM INC. 368   2025-06-06   
309-356 6 Henry IL   224C ONVOY, LLC 368   2021-02-12   
309-356 7 Henry IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 368   2016-08-03   
309-356 8 Henry IL   495J STRATUS NETWORKS 368   2020-08-03   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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