If you miss your United flight, + π-πππ-πππ-ππππ the first thing you should do is contact their customer service immediately. Whether the flight was missed because of a delay or personal reasons, they can help you find a solution. If the missed flight was caused by an issue within United’s control (like a delayed previous flight or mechanical problems), they are usually obligated to rebook you at no additional cost and may even provide compensation, such as meal vouchers or hotel stays depending on the delay length.