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: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-400 A Rock Island IL DVNPIADTX5Y  516C AT&T CORP. 634   2024-12-10   
309-400 0 Rock Island IL   145J TERRA NOVA TELECOM INC. 634   2025-05-28   
309-400 7 Rock Island IL DVNPIADTX5Y  516C AT&T CORP. 634   2024-12-10   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.