Montreal Convention

The Montreal Convention is the international treaty that governs airline liability for death and bodily injury, damage to or loss of baggage and cargo, and delay on international flights. Formally known as the Convention for the Unification of Certain Rules for International Carriage by Air, it was concluded at Montreal on May 28, 1999 under the auspices of the International Civil Aviation Organization, entered into force in November 2003, and has been ratified by over 130 states including all European Union members, the United States, China, Japan, Australia, and Canada. The convention modernised and consolidated a fragmented patchwork of earlier agreements, principally the 1929 Warsaw Convention and its various protocols, into a single coherent instrument.

What Is the Montreal Convention?

The Montreal Convention establishes a two-tier liability system for passenger claims arising from death or injury. Under the first tier, covering claims up to 128,821 Special Drawing Rights (approximately 175,000 US dollars at typical exchange rates), the airline is strictly liable and cannot invoke defences based on due diligence or absence of fault. Under the second tier, covering claims above that threshold, the airline may escape liability only by proving that the damage was not due to its negligence or that it was solely due to the negligence or wrongful act of a third party. This structure effectively ensures that victims of aviation accidents receive prompt compensation up to a substantial threshold without the burden of proving airline negligence.

How It Works in Practice

For checked baggage claims, the Montreal Convention caps airline liability at 1,288 SDRs (roughly 1,750 US dollars) per passenger, unless the passenger has made a special declaration of value at check-in and paid any applicable supplementary charge. For carry-on baggage, the same limit applies, but the airline is only liable if the passenger proves that the damage was caused by the carrier's fault. For cargo, the liability limit is 22 SDRs per kilogram. For delay claims — covering financial losses caused by late arrival of passengers, baggage, or cargo — the limits are 5,346 SDRs for passengers and the baggage limits for property. Airlines frequently attempt to disclaim liability for delay by citing extraordinary circumstances, though the convention's text requires airlines to prove they took all necessary measures to avoid the delay.

Why It Matters

The Montreal Convention matters because it creates the legal floor for passenger claims across the entire international aviation system. Without it, passengers would face a chaotic landscape of inconsistent national laws, many far less generous. The convention also drives airline insurance requirements: every carrier operating international routes must maintain insurance coverage adequate to satisfy Montreal Convention claims, and many insurance policies in the market are structured around the convention's liability architecture. For courts, the convention preempts domestic law for claims within its scope, meaning a US passenger cannot sue a US airline under US tort law for death occurring on an international flight — only the convention's framework applies.

Key Facts and Figures

• The SDR liability limits are reviewed every five years; the most recent revision took effect in December 2019.
• 137 states had ratified the Montreal Convention as of 2024, covering more than 99 percent of international air traffic.
• The United States ratified the convention in 2003, replacing the Warsaw Convention system for all international flights to and from the US.
• Before Montreal, the Warsaw Convention's death liability cap was a mere 75,000 US dollars, a figure set in 1955 that had become woefully inadequate by the time of modernisation.
• Airlines such as Japan Airlines, Lufthansa, and Air France established voluntary commitments in the 1990s to waive the Warsaw cap for flights to the US — a direct precursor to the Montreal regime.
• The convention requires airlines to provide advance payments to natural persons entitled to claim compensation for death or injury, to meet immediate economic needs.

Related Concepts

Warsaw Convention, EU 261 Regulation, ICAO, Denied Boarding Compensation, Air Carrier Certificate