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: 284

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-284 A Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 0 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 1 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 2 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 3 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 4 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 5 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 6 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 7 Chicago Zone 01-Franklin IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2019-02-24   
312-284 8 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-284 9 Chicago Zone 01-Franklin IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2019-02-24   

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

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