Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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 CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2013-05-23   
331-281 1 Naperville IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-04-12   
331-281 2 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 3 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 4 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 5 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 6 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 7 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 8 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   
331-281 9 Naperville IL NPVLILNEDS0  9329 ILLINOIS BELL TEL CO 358   2012-11-24   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.