Local Calling Guide

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

NXX: 850

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-850 A Big Rock IL CHCGIL24DS6  224C ONVOY, LLC 358      
331-850 1 Big Rock IL CHCGILWUKMD  939H COMMIO, LLC 358   2022-02-24   
331-850 2 Big Rock IL CHCGILNEXIX  506J TWILIO INTERNATIONAL, INC. 358   2021-08-30   
331-850 3 Big Rock IL   318J COMCAST IP PHONE, LLC 358   2024-04-18   
331-850 5 Big Rock IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-08-09   
331-850 6 Big Rock IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2024-01-11   
331-850 8 Big Rock IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2021-06-27   
331-850 9 Big Rock IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2021-10-01   

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

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