Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 574

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-574 A Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-574 0 Chicago Zone 01-Franklin IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358      
312-574 1 Chicago Zone 01-Franklin IL CHCGILDTDS3  5447 ACCESS ONE, INC. - IL 358      
312-574 2 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-574 3 Chicago Zone 01-Franklin IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358      
312-574 4 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-574 5 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-574 6 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-574 7 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-574 8 Chicago Zone 01-Franklin IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358      
312-574 9 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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