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: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 705

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-705 A Chicago Zone 01-Wabash IL CHCGIL24DS0  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.