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: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-340 A Bensenville IL CHCGIL24DS6  224C ONVOY, LLC 358   2025-12-27   
331-340 0 Bensenville IL CHCGIL24DS6  224C ONVOY, LLC 358   2025-12-27   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.