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: 757

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-757 A Lemont IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-757 0 Lemont IL   073H TELNYX LLC 358   2017-04-24   
331-757 1 Lemont IL   224C ONVOY, LLC 358   2017-06-23   
331-757 2 Lemont IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2017-04-27   
331-757 3 Lemont IL   224C ONVOY, LLC 358   2018-01-15   
331-757 4 Lemont IL   7196 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL 358   2017-05-15   
331-757 5 Lemont IL   318J COMCAST IP PHONE, LLC 358   2016-09-12   
331-757 6 Lemont IL   224C ONVOY, LLC 358   2018-01-15   
331-757 7 Lemont IL   516C AT&T CORP. 358   2016-10-24   
331-757 8 Lemont IL   6529 T-MOBILE USA, INC. 358   2016-09-11   
331-757 9 Lemont IL   6529 T-MOBILE USA, INC. 358   2016-09-11   

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

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