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: 281

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-281 A Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358      
331-281 0 Naperville IL   318J COMCAST IP PHONE, LLC 358   2013-05-23   
331-281 1 Naperville IL   224C ONVOY, LLC 358   2013-04-12   
331-281 2 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 3 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 4 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 5 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 6 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 7 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 8 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 9 Naperville IL   9329 ILLINOIS BELL TEL CO 358   2012-11-24   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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