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: 870

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-870 A Chicago Zone 01-Calumet IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-870 1 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 2 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 3 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 4 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 5 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 6 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 7 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      
312-870 8 Chicago Zone 01-Calumet IL CHCGILFRDS1  9329 ILLINOIS BELL TEL CO 358   2000-11-03   
312-870 9 Chicago Zone 01-Calumet IL   4604 FIRST COMMUNICATIONS, LLC - IL 358      

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

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