US flight delay compensation: the honest answer

There is no US law that pays cash for flight delays. Anyone telling you otherwise is selling something. What DOES exist: (1) a DOT-enforced automatic cash refund when your flight is cancelled or "significantly changed" and you don't travel; (2) airline-specific commitments (rebooking, meals, hotels) in their customer service plans; (3) — the big one — foreign rules that cover US-airline flights: any flight departing the EU (up to €600), the UK (up to £520), Canada (up to C$1,000), Turkey, Brazil, or India follows THOSE rules, even on American, Delta or United.