Under the EU261/2004 regulation (and its UK equivalent), "Air Traffic Control (ATC) delays" are almost always classified as "Extraordinary Circumstances," meaning passengers are generally not entitled to financial compensation (the €250–€600 payout). The reasoning is that ATC decisions are outside the airline's "actual control," as they are mandated by government safety authorities to manage congestion or weather-related spacing. However, the airline is still legally obligated to provide "Duty of Care" regardless of the reason for the delay. This means that if an ATC delay keeps you at the airport for more than 2 hours, the airline must provide food and drink vouchers and two phone calls or emails. If the delay forces an overnight stay, they must provide hotel accommodation and transport. In 2026, if an airline claims an ATC delay but other flights are departing normally, you may be able to challenge the claim. If the "ATC delay" was actually caused by the airline's own scheduling failures or crew shortages, you may still be eligible for full compensation.