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: 355

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-355 A Gridley IL BLTNILXDXPX  846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366      
309-355 1 Gridley IL BLTNILXDXPX  846F MEDIACOM TELEPHONY OF ILLINOIS, LLC - IL 366   2019-07-12   
309-355 5 Gridley IL   145J TERRA NOVA TELECOM INC. 366   2025-05-27   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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