Western Sydney International (Nancy-Bird Walton) Airport (IATA: WSI), also known as Western Sydney Airport or Badgerys Creek Airport, is a new international airport currently under construction within the suburb of Luddenham and Badgerys Creek, New South Wales, Australia.

The site was officially designated by the Federal Government on 15 April 2014, after decades of debate on the location of another airport within Greater Sydney. The airport is planned to have 24-hour and curfew-free operations and will supplement Kingsford Smith Airport, which has reached capacity due to a legislated curfew and flight caps.

The first stage of construction on the new airport began on 24 September 2018, and the first stage is expected to be complete and open by December 2026.