Congestion at major airports is a growing global challenge. Most airport slots are “grandfathered,” meaning existing users de facto hold them in perpetuity provided they meet a “use-it-or-lose-it” threshold of 80% (known as the 80:20 rule). The current system is often criticized for limiting turnover and new entry.

In this article, Consultant Dr. Tuba Toru Delibasi and Economic Analyst Yasmine Frizlen, with contributions from Senior Managing Director Richard Marsden, Managing Directors Daniel Hanson and Dr. Soren Tang Sorensen, and Director Hans-Martin Ihle examine the UK’s consultation, which explores options like limiting slot leasing, changing use-it-or-lose-it thresholds, and introducing auctions. In principle, a well-designed auction process has the potential to allocate capacity to airlines that will utilize it most effectively and generate the greatest societal value.