Local Calling Guide

Area code/prefix search

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

NXX: 363

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-363 A Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 0 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 1 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 2 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 3 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 4 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 5 Chicago Zone 01-Monroe IL CHCGILACGT0  8702 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 358      
312-363 6 Chicago Zone 01-Monroe IL CHCGILWUX6X  460K FIRST COMMUNICATIONS, LLC 358   2004-06-06   
312-363 7 Chicago Zone 01-Monroe IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   
312-363 8 Chicago Zone 01-Monroe IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   
312-363 9 Chicago Zone 01-Monroe IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2004-07-15   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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