Local Calling Guide

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NPA: 773 [Rate centres in NPA 773] [Dial plan for NPA 773]

NXX: 570

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
773-570 A Chicago Zone 11-O'Hare IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
773-570 0 Chicago Zone 11-O'Hare IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2008-12-12   
773-570 1 Chicago Zone 11-O'Hare IL   224C ONVOY, LLC 358   2014-09-29   
773-570 2 Chicago Zone 11-O'Hare IL   224C ONVOY, LLC 358   2014-09-29   
773-570 3 Chicago Zone 11-O'Hare IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2005-07-14   
773-570 4 Chicago Zone 11-O'Hare IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
773-570 5 Chicago Zone 11-O'Hare IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2005-07-14   
773-570 6 Chicago Zone 11-O'Hare IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2005-07-14   
773-570 7 Chicago Zone 11-O'Hare IL   224C ONVOY, LLC 358   2012-10-01   
773-570 8 Chicago Zone 11-O'Hare IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2015-04-16   
773-570 9 Chicago Zone 11-O'Hare IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2015-12-03   

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

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