A delayed bag becomes a lost bag after 21 days on an international trip, sooner under many airlines’ rules. How the days are counted and what the claim becomes.
Airlines call a missing bag “delayed” for as long as they can, because a delay claim is smaller than a loss claim. The rules set a point where that stops.
International trips: the Montreal Convention lets you treat a bag as lost once 21 days have passed from the date it should have arrived. From that day you can claim the full contents up to the cap, not just interim purchases.
Airline rules: several airlines declare a bag lost sooner in their own terms, some after five days, most after 21 to 30. Your airline’s page on this site shows its number.
What changes: your claim switches from “what I had to buy” to “everything that was in the bag”, and the deadline for the written claim is now measured from the day the bag was declared lost rather than from delivery. If the bag later turns up, the airline can ask for items back or offset what it paid.
Work out your own claim → Two minutes to your amount and deadlines.
From the date the bag should have arrived, which is the date your flight landed, not the date you reported it or the date the airline last updated its tracking. A bag that should have come out on 1 September may be treated as lost from 22 September. The airline’s tracing system will often show a bag as “located” or “on the next flight” for days; that changes nothing about the count.
Then the lost-bag claim opens that day. Several airlines’ own rules treat a bag as lost after five days and open a contents claim then; others hold to 21 or 30. Your airline’s page on this site shows its number next to the day of the check. An airline’s earlier date helps you; it can never push the date past the treaty’s 21 days on an international trip.
The airline may ask for the items back or offset what it paid, and the terms of most settlements say so. Keep the settlement letter. If the bag comes back with things missing or damaged, the difference stays claimable. Do not refuse a returned bag in the hope of keeping a larger payment; accept it, inventory it, and adjust the claim in writing.
No, and most do not. Tracing systems keep a bag “in process” indefinitely, and the call centre will say it is still being looked for. The treaty does not wait for the airline’s admission: once the days have run, you may treat the bag as lost and claim accordingly. Put the date in the letter and the arithmetic that follows from it; the airline can rebut it only by delivering the bag.
Not a complaint window like the 7 and 21 days for damage and delay. The outer wall is two years from the date of arrival to bring an action, and courts treat it as absolute. Do not let a claim that has been “under review” for months drift toward that date; escalate to a DOT complaint and, if needed, small-claims court well inside it.
No. Send the interim-expense claim now with a line saying you will claim the contents if the bag is not delivered by day 21. The letter this site builds does that.