For a purely domestic flight in the USA, there is no federally required compensation as there is in some other parts of the world.
The US Department of Transportation explains:
There are no federal laws requiring airlines to provide passengers with money or other compensation when their flights are delayed. Each airline has its own policies about what it will do for delayed passengers. If your flight is experiencing a long delay, ask airline staff if they will pay for meals or a hotel room. While some airlines offer these amenities to passengers, others do not provide any amenities to stranded passengers.
However, if you are on the plane for more than two hours, various consumer protections do kick in:
At two hours, the flight must offer food and water.
U.S. airlines must provide passengers with food and water no later than two hours after the tarmac delay begins. While the aircraft remains on the tarmac lavatories must remain operable and medical attention must be available if needed.
At three hours, the flight must return to the gate unless safety issues prevent it.
Some flights are delayed on the airport "tarmac" before taking off or after landing. DOT rules prohibit most U.S. airlines from allowing a domestic flight to remain on the tarmac for more than three hours unless:
- the pilot determines that there is a safety or security reason why the aircraft cannot taxi to the gate and deplane its passengers, or
- Air traffic control advises the pilot that taxiing to the gate (or to another location where passengers can be deplaned) would significantly disrupt airport operations.
The DOT has an extensive explanation of the (limited) air passenger rights in the US.
