Local Calling Guide

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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 220

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-220 A Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-220 0 Aurora IL   6529 T-MOBILE USA, INC. 358   2011-08-26   
331-220 1 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-08-26   
331-220 2 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-08-26   
331-220 3 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-08-26   
331-220 4 Aurora IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-10-08   
331-220 5 Aurora IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-10-08   
331-220 7 Aurora IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2026-05-02   
331-220 9 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-08-26   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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