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: 236

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-236 A Wheaton IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-236 0 Wheaton IL   224C ONVOY, LLC 358   2017-06-26   
331-236 1 Wheaton IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2018-12-14   
331-236 2 Wheaton IL   197D VONAGE AMERICA LLC 358   2020-10-15   
331-236 3 Wheaton IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2019-08-29   
331-236 4 Wheaton IL   197D VONAGE AMERICA LLC 358   2020-10-15   
331-236 5 Wheaton IL   224C ONVOY, LLC 358   2019-07-07   
331-236 6 Wheaton IL   224C ONVOY, LLC 358   2019-07-07   
331-236 7 Wheaton IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2017-11-04   
331-236 8 Wheaton IL   6529 T-MOBILE USA, INC. 358   2017-06-02   
331-236 9 Wheaton IL   6529 T-MOBILE USA, INC. 358   2017-06-02   

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

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