Any Passenger whose flight is cancelled, shall have the choice of either: Re-routing, under comparable transport conditions, to the destination of the ticket presented at check-in at the earliest opportunity or at a later date at the passenger’s convenience, subject to availability of seats; or A refund payable to the person who purchased the ticket. This refund applies to only that part or parts of the journey not flown, unless you can prove that the flown part(s) of the journey no longer serves any purpose in relation to your travel plans. Where relevant, the airline must also provide a return flight to the first point of departure at the earliest opportunity.
According to recent data, so far this year, 2.5 percent of all U.S. domestic flights were canceled, and only about 0.23 percent have been diverted to an airport other than the original destination. While these numbers are the highest they’ve been since 2015, your odds of being canceled are still slight, but you can face some real hassles if it does happen. You might be surprised to find that, in the U.S., no federal law or regulation specifies what "rights" you have when an airline cancels your flight. The only federal laws or regulations applying to so-called "irregular operations" deal narrowly with bumping due to an oversold flight and extended tarmac delays. Your rights as a canceled passenger derive solely from the airlines' contracts of carriage, plus relevant principles of general contract law.