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: 253

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-253 A Lemont IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-253 0 Lemont IL   224C ONVOY, LLC 358   2014-12-30   
331-253 1 Lemont IL   224C ONVOY, LLC 358   2014-12-30   
331-253 2 Lemont IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2015-07-02   
331-253 3 Lemont IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2015-10-30   
331-253 4 Lemont IL   224C ONVOY, LLC 358   2016-04-16   
331-253 5 Lemont IL   224C ONVOY, LLC 358   2016-04-16   
331-253 6 Lemont IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2016-07-16   
331-253 7 Lemont IL   6529 T-MOBILE USA, INC. 358   2016-08-07   
331-253 8 Lemont IL   6529 T-MOBILE USA, INC. 358   2015-12-25   
331-253 9 Lemont IL   6529 T-MOBILE USA, INC. 358   2014-12-11   

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

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