The treaty behind every international baggage claim: what it covers, the limit, and the three deadlines.
If any flight on your ticket crossed a border, the Montreal Convention of 1999 governs your baggage claim. It applies to the whole trip, including a domestic connection on the same ticket, and it overrides the airline’s own terms wherever they say less.
What it says. The airline is liable for checked baggage that is lost, delayed or damaged while in its care (Article 17). Liability is capped at 1,519 SDR per passenger, about $2,081 (Article 22). A bag not delivered within 21 days of the date it should have arrived may be treated as lost (Article 17(3)).
The deadlines (Article 31 and 35): written complaint within 7 days of receipt for damage; within 21 days of receipt for delay; and two years from the date of arrival to bring a claim in court. Miss the written-complaint deadline and the airline can refuse the claim outright, so the letter matters more than the phone call.
You do not need to cite the treaty to be covered by it, but a letter that does tends to be answered by someone who knows the rules rather than by a template.
Work out your own claim → Free. Takes about ten minutes.
Yes. The whole journey on one ticket is international carriage.
Nearly every country with scheduled airline service, including the United States, Canada, the UK, the EU, and most of Asia and Latin America.