US airlines aren't federally required to pay cash compensation for cancellations the way some international regulations (like the EU's rules) mandate. Instead, US airlines are contractually obligated, through their own customer service commitments, to rebook you on the next available flight at no extra cost, or issue a full refund if you choose not to travel.
Under current US Department of Transportation rules, if an airline cancels or significantly changes your flight, you're entitled to a full refund back to your original payment method if you decide not to accept the rebooking — even for a normally non-refundable ticket.
For cancellations within the airline's control (like a mechanical issue or staffing problem, as opposed to weather), many major US airlines have committed to covering meals, hotel accommodation, and ground transportation for significant delays — check the specific airline's customer service commitment, since coverage isn't standardized across all carriers.
