Passenger rights on a cancelled flight depend largely on where the flight was departing from or the airline's home country. Under UK/EU 261 regulations, if your flight is cancelled, the airline must offer you a choice between a full refund or re-routing to your destination at the earliest opportunity. If you choose re-routing and have to wait overnight, the airline is legally obligated to provide "duty of care," which includes hotel accommodation, transport to the hotel, and meals. Furthermore, if the cancellation was the airline's fault (not "extraordinary circumstances" like weather) and they notified you less than 14 days before departure, you may be entitled to cash compensation ranging from £220 to £520 ($250 to $600) depending on the flight distance. In the United States, rights are more limited; while the DOT requires airlines to refund your ticket if you choose not to travel after a cancellation, they are not legally mandated to provide meals or hotels, though many will do so as a matter of policy. Always ask for a written statement of your rights at the airport and keep all receipts for out-of-pocket expenses to claim back later.