Local Calling Guide

Area code/prefix search

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Chicago Zone 01-Monroe, IL

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
312-226 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-243 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-260 A BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 0 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 1 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 2 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 3 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 4 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 5 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 6 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 7 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2005-12-12   
312-260 8 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-260 9 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-279 A BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-355 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 0 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-361 1 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-07-14   
312-361 2 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 3 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-07-14   
312-361 4 BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2011-06-23   
312-361 5 CHCGIL24DS6  224C ONVOY, LLC 358   2010-10-27   
312-361 6 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 7 BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2011-06-23   
312-361 8 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-361 9 DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-10-27   
312-363 A CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 0 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 1 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 2 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 3 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 4 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 5 CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 6 CHCGILWUX6X  460K FIRST COMMUNICATIONS, LLC 358   2004-06-06   
312-363 7 ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   
312-363 8 ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   
312-363 9 ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   
312-413 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-421 A CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-432 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-433 A CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 0 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 1 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 2 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 3 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 4 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 5 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 6 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 7 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 8 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-433 9 RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-01-14   
312-455 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-470 A BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 0 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 1 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 2 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 3 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 4 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 5 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 6 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-11-20   
312-470 7 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 8 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-470 9 BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-491 A CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-492 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 0 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 1 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 2 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 3 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 4 CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-10-25   
312-492 5 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 6 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 7 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 8 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-492 9 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-563 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 A CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 0 CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-569 1 OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2002-06-24   
312-569 2 ELGNILOTGT5  5562 METROPCS, INC. 358   2017-02-05   
312-569 3 CHCGIL24DS6  224C ONVOY, LLC 358   2002-06-24   
312-569 4 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2002-06-24   
312-569 5 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 6 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 7 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 8 CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-569 9 CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-572 A CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 0 ELGNILOTGT5  5562 METROPCS, INC. 358   2017-02-05   
312-572 1 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 2 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 3 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 4 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 5 CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      
312-572 6 CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2009-09-29   
312-572 7 CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2007-12-14   
312-572 8 CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2009-09-29   
312-572 9 CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-601 A BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-633 A CHCGILMODS0  9329 ILLINOIS BELL TEL CO 358      

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Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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