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: 230

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-230 A Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 0 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 1 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 2 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 3 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 4 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 5 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 6 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 7 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      
312-230 8 Chicago Zone 01-Franklin IL CHCGILMF4MD  5562 METROPCS, INC. 358   2016-02-15   
312-230 9 Chicago Zone 01-Franklin IL CHCGILFRDS0  9329 ILLINOIS BELL TEL CO 358      

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

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