Yes, you can sue an airline in Europe, and the process is actually more consumer-friendly than in many other regions due to the EC 261/2004 (and the UK equivalent UK261) regulations. These laws provide high-value, standardized "Fixed Compensation" for delays over 3 hours, cancellations, and denied boarding. If an airline refuses to pay your legitimate claim, you don't necessarily have to hire a private lawyer; you can take them to the National Enforcement Body (NEB) of the country where the flight took place or use a "Small Claims" court procedure, which is low-cost and designed for individuals. In 2026, many "Claim Agencies" operate on a "No-Win, No-Fee" basis, taking a 25-30% cut to handle the legal legwork for you. It is a peer-to-peer essential to know that you can only sue for "Extraordinary Circumstances" (like weather or strikes) if the airline failed in its "Duty of Care" (providing food and hotels). For standard mechanical delays, the law is firmly on your side, making a legal challenge a high-probability "win" if you have the patience to see the process through.