I built it after realising how many people sit through a 4-hour delay or a cancellation and never claim the compensation they're owed. Under EU261 and UK261 it can be up to 600 per passenger.
Check for free whether you may be owed up to €600 for a delayed or cancelled flight in the EU, UK or Turkey. Enter the flight number and date: Dueply drafts the letter to the airline, with no commission.
