Local Calling Guide

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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-399 A Downers Grove IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-399 0 Downers Grove IL CHCGIL24MMD  515J IP HORIZON LLC 358   2021-06-12   
331-399 1 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 2 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 3 Downers Grove IL CHCGILNEXIX  506J TWILIO INTERNATIONAL, INC. 358   2021-04-13   
331-399 4 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2021-06-28   
331-399 5 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 6 Downers Grove IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2021-03-27   
331-399 7 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2021-11-14   
331-399 8 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2021-11-14   
331-399 9 Downers Grove IL CHCGILWURMD  965H FRACTEL, LLC 358   2021-03-26   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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