Montreal Convention: Carrier Liability and Claims Basics
A carrier's default liability for lost or damaged cargo is capped by international treaty at 22 SDR per kilogram — usually far below actual value, unless declared value is used.
Get a Rate22 SDR/kg
Default cargo liability limit
Article 22(3)
Montreal Convention cargo liability provision
1999
Convention adoption year
2 years
Time limit to bring an action (Article 35)
A capped, not full, liability regime
The Montreal Convention (1999) — in force for Canada via the Carriage by Air Act — governs an international air carrier's liability for cargo loss, damage, and delay. Article 22(3) caps that liability at 22 Special Drawing Rights (SDR, an IMF-defined unit of account) per kilogram of the affected cargo, regardless of the goods' actual value, unless the shipper declared a higher value for carriage and paid a supplementary charge at booking.
This cap applies per kilogram of the specific cargo affected, not per shipment as a whole — a partial loss within a multi-piece shipment is compensated based on the weight of the affected pieces, not the full AWB weight.
Article 35 sets a strict two-year limitation period from the date of arrival (or from when the aircraft ought to have arrived) to bring an action — separate from and typically shorter than the notice-of-claim deadlines carriers set in their own conditions of carriage, which are often 14 days for damage and 21 days for delay. Missing the carrier's own notice deadline can bar a claim well before the two-year Convention limit is reached.
Montreal Convention, Article 22(3)
Default cargo liability is capped at 22 SDR per kilogram — declare a higher value if your cargo is worth more
For high-value cargo, the standard liability limit is very likely far below actual replacement value. Declaring a higher value for carriage at booking, and paying the associated supplementary charge, is the mechanism to increase the carrier's liability exposure beyond the default cap.
Source: Convention for the Unification of Certain Rules for International Carriage by Air (Montreal Convention, 1999), Article 22(3); Carriage by Air Act (R.S.C. 1985, c. C-26).
Worked example
A worked example: partial loss on a 50kg shipment
Take a 50kg shipment where 10kg worth of cargo is confirmed lost in transit, with no declared value for carriage on the AWB.
Under Article 22(3), the carrier's default liability is 22 SDR × 10kg (the affected weight, not the full 50kg) — a fixed ceiling regardless of what that specific 10kg of goods was actually worth commercially. SDR values fluctuate against the Canadian dollar; the exact CAD figure is calculated at the time of settlement, not fixed in advance.
Had the shipper declared a higher value for carriage on this specific shipment and paid the associated charge, the carrier's liability would extend to that declared amount instead of the default cap — this is the only standard mechanism to increase recovery beyond 22 SDR/kg under the Convention framework.
What UAL flags before booking
We flag the default liability cap for shippers moving high-value cargo and confirm whether declared value for carriage — or separate cargo insurance — is the right tool for the specific shipment's value. See our cargo insurance basics guide for how that compares to declared value.
Frequently asked questions
No — declared value for carriage increases the carrier's own liability cap under the Montreal Convention framework and is paid to the carrier as a supplementary charge. Cargo insurance is a separate policy from an insurer, independent of the carrier's liability regime. See our cargo insurance basics guide for the distinction in full.
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Source: Montreal Convention (1999), Articles 22(3) and 35; Carriage by Air Act (R.S.C. 1985, c. C-26). Last verified July 2026.
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