Local Calling Guide

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

NXX: 931

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-931 A Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      
312-931 0 Chicago Zone 01-Franklin IL CHCGILMF4MD  5562 METROPCS, INC. 358   2011-01-05   
312-931 1 Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      
312-931 2 Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      
312-931 3 Chicago Zone 01-Franklin IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2022-01-07   
312-931 4 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2011-01-05   
312-931 5 Chicago Zone 01-Franklin IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-09-20   
312-931 6 Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      
312-931 7 Chicago Zone 01-Franklin IL CHCGILMF4MD  5562 METROPCS, INC. 358   2011-01-05   
312-931 8 Chicago Zone 01-Franklin IL   197D VONAGE AMERICA LLC 358   2024-03-25   
312-931 9 Chicago Zone 01-Franklin IL CHCGILFRDS4  9329 ILLINOIS BELL TEL CO 358      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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