Local Calling Guide

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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-450 5 Chicago Zone 01-Wabash IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358      
312-450 6 Chicago Zone 01-Wabash IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2007-09-25   
312-450 7 Chicago Zone 01-Wabash IL CHCGIL24DS6  224C ONVOY, LLC 358   2009-09-04   
312-450 8 Chicago Zone 01-Wabash IL CHCGILDTKMD  5447 ACCESS ONE, INC. - IL 358   2009-09-04   
312-450 9 Chicago Zone 01-Wabash IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2009-01-27   
312-451 A Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-451 0 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-11-18   
312-451 1 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-09   
312-451 2 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-09   
312-451 3 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-09   
312-451 4 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-09   
312-451 5 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-09   
312-451 6 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-08-24   
312-451 7 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-09-07   
312-451 8 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2003-09-07   
312-451 9 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2005-08-01   
312-452 A Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 0 Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 1 Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 2 Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 3 Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 4 Chicago Zone 01-Calumet IL   624H ONVOY SPECTRUM, LLC 358   2025-10-28   
312-452 5 Chicago Zone 01-Calumet IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-27   
312-452 6 Chicago Zone 01-Calumet IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-27   
312-452 7 Chicago Zone 01-Calumet IL   224C ONVOY, LLC 358   2026-01-05   
312-452 8 Chicago Zone 01-Calumet IL   224C ONVOY, LLC 358   2026-01-05   
312-452 9 Chicago Zone 01-Calumet IL   224C ONVOY, LLC 358   2026-01-05   
312-453 A Chicago Zone 01-Wabash IL EGVGILIFDS1  7196 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL 358      
312-454 A Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-455 A Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-456 A Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      
312-457 A Chicago Zone 01-Wabash IL CHCGILBWCM2  9748 AMERICAN MESSAGING SERVICES, LLC 358      
312-458 A Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 0 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 1 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 2 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 3 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 4 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 5 Chicago Zone 01-Franklin IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2016-02-28   
312-458 6 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 7 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 8 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-458 9 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-459 A Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-459 0 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-09-16   
312-459 1 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-09-16   
312-459 2 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-09-16   
312-459 3 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2011-09-16   
312-459 4 Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-10-08   
312-459 5 Chicago Zone 01-Calumet IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2025-12-04   

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Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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