Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-221 A Elmhurst IL EMHRILETDS0  9329 ILLINOIS BELL TEL CO 358      
331-221 0 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 1 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 2 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 3 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 4 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 5 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 6 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 7 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 8 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   
331-221 9 Elmhurst IL   9329 ILLINOIS BELL TEL CO 358   2009-03-05   

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

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