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: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 337

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-337 A Platte Center NE OMAHNENWXPX  549E ONVOY, LLC - NE 644      
531-337 3 Platte Center NE OMAHNENWXPX  549E ONVOY, LLC - NE 644   2023-10-06   
531-337 7 Platte Center NE   145J TERRA NOVA TELECOM INC. 644   2025-07-14   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.