NEW RULES FOR
NEW SKIES

Modernise airport slot policy now

A five-airplane rating graphic with three airplanes filled in blue and two in white, representing a 3 out of 5 rating—perfect for visualizing Airport Slots availability or performance.

Airport slot rules were designed for a different aviation era.

Today, more airports face capacity constraints, more airlines compete for access, and demand for air travel continues to grow. ACI World is calling for airport slot rules to be modernised.

A system that has not kept pace

AT THE WORLD'S BUSIEST AIRPORTS, THERE IS NOT ENOUGH CAPACITY FOR EVERY AIRLINE THAT WANTS TO FLY.

The basic structure of today’s slot system was established in the 1970s, when governments played a stronger role in shaping air services. The rules have been updated over time, but the basic principles of the slot system remain the same.

As competition for scarce airport capacity has grown, those principles have increasingly favoured airlines already at an airport, leaving limited room for new or expanding competitors.

1974

The year the basic structure of the slot rules was established

+36%
Growth in the number of congested airports over the last decade

~2x
Projected growth in global passenger traffic by 2046

Airport access is a public policy issue

Airport slots do more than organise schedules. Their effects extend well beyond day-to-day operations.

Routes and connectivity

Slots shape which routes airlines can offer and which markets they can serve.

Competition

Slots affect the ability of airlines to enter, grow and compete.

Passengers, communities and economies

How scarce airport capacity is used affects the people and places airports serve.

How should airport slot policies be modernised?

Give airports a voice

Airports should have a structured role in how scarce capacity is managed, while slot coordinators continue to act independently and neutrally.

Make the system more transparent

There should be greater visibility of how slots are allocated, used and exchanged over time for airlines, airports, policymakers and other relevant stakeholders.

Reform how slots are allocated and kept over time

Local priorities should help guide how new slots are allocated, while continued access to historic slots should be periodically reviewed to support the efficient use of scarce airport capacity.

Bring slot mobility within the system

Slot exchanges and transfers should be more transparent and subject to appropriate oversight. Where slot transactions generate monetary value, part of that value should contribute to improving or expanding airport capacity.

Modernisation does not mean replacing the global slot system. It means making sure the system can evolve as airport capacity becomes increasingly scarce.

Perspectives from across the ACI Federation

ACI Europe

Olivier Jankovec

The white paper

The full case for modernising airport slot policy — for policymakers, regulators and anyone shaping the future of aviation.

Cover of a white paper titled Airport Slot Policy, by Airports Council International, featuring airplane icons and a dotted line representing Airport Slots, with publication year 2026.

How airport slots currently work?