Local Calling Guide

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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 CHCGILWUJMD  073H TELNYX LLC 358   2017-04-24   
331-757 1 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-06-23   
331-757 2 Lemont IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2017-04-27   
331-757 3 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2018-01-15   
331-757 4 Lemont IL EGVGILIFDS1  7196 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL 358   2017-05-15   
331-757 5 Lemont IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2016-09-12   
331-757 6 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2018-01-15   
331-757 7 Lemont IL CHCGILCLXOX  516C AT&T CORP. 358   2016-10-24   
331-757 8 Lemont IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2016-09-11   
331-757 9 Lemont IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2016-09-11   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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