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: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-666 A Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358      
331-666 0 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2019-10-23   
331-666 1 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2019-10-23   
331-666 2 Aurora IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2020-11-02   
331-666 3 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2021-07-15   
331-666 4 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2021-07-15   
331-666 5 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2019-06-07   
331-666 6 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-11-26   
331-666 7 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2019-06-07   
331-666 8 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2019-10-23   
331-666 9 Aurora IL CHCGIL24XMD  495J STRATUS NETWORKS 358   2020-09-20   

Last updated: Sun, 01 Nov 2026 02:11:49 UTC

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