Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 206

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-206 A Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-206 0 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-11-26   
331-206 7 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-11-26   
331-206 8 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-11-26   
331-206 9 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2023-11-25   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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