Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 630 [Rate centres in NPA 630] [Dial plan for NPA 630]

NXX: 574

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
630-574 A Oak Brook IL OKBRILOADS0  9329 ILLINOIS BELL TEL CO 358      
630-574 0 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 1 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 2 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 3 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 4 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 5 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 6 Oak Brook IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358      
630-574 7 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 8 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      
630-574 9 Oak Brook IL   9329 ILLINOIS BELL TEL CO 358      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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