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: 537

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-537 A Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 0 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 1 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 2 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 3 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 4 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 5 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 6 Chicago Zone 01-Canal IL CHCGILCPDS5  4717 PAETEC COMMUNICATIONS, INC. - IL 358   2009-04-08   
312-537 7 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 8 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-537 9 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      

Last updated: Fri, 13 May 2022 22:16:13 UTC

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