A passenger standing at a US gate watching the board change has usually been told two things that are both wrong: that the airline owes them nothing because the weather did it, and that they are entitled to a payout because a friend in Europe once got one. The US rules are narrower than the second story and wider than the first, and they are short enough to read in ten minutes. They give a refund, they give a percentage of the fare for one specific thing, and for everything else they give whatever the airline has promised in its own plan.
The refund is the backbone, and it is automatic
The rule that matters most to a cancelled passenger is the refund rule. It reaches any cancelled flight, and any flight delayed or changed significantly, to, from or within the United States, and it applies to a nonrefundable ticket. What triggers it is the passenger declining what the airline offers: if you will not take the delayed flight, the rebooking or the voucher, the fare goes back, taxes and ancillary fees included. It is described in the regulation as automatic, meaning the airline is not entitled to wait for you to ask. The practical consequence is that a voucher is an offer and never an obligation, and accepting one closes the door on the cash.
There is no payment for the delay itself, and that is the whole difference
The part of Title 14 that deals with this is titled Refunds, and it stops at the fare. Nothing in it pays a passenger a sum on top of their money back because their evening was ruined, their meeting was missed or they landed nine hours late. That is the single largest difference between flying inside the United States and flying under the UK regime, where a long delay carries a fixed sum that has nothing to do with what the ticket cost. This site records the US position as an absence on the section that would carry such a rule if it existed, rather than as a claim about what airlines do.
One thing does pay a sum, and it is being denied boarding
Where a flight is oversold and a passenger is denied boarding against their will, the regulation sets the payment as a percentage of the fare with a cash ceiling, and it scales with how late the airline gets you there instead. Nothing is owed if the substitute arrives within an hour; the lower tier applies where it arrives between one and two hours late; the higher tier applies beyond that. It is worth knowing precisely because it is the one place the US scheme behaves like the European one, and because a passenger who volunteers for a seat at the gate has accepted a negotiated offer instead and given that entitlement up.
Meals, a hotel and a straight answer are the airline's promise, not the law's
The rule that governs an airline's Customer Service Plan lists the subjects the plan must cover and sets a minimum standard for each. Meals during a delay, a hotel room overnight and ground transport to it are not among them. Several US carriers do promise them, and since those promises sit in a published plan they are contractual and worth quoting back. What the rules do guarantee is an answer: a carrier must acknowledge a written complaint within thirty days and send a substantive reply within sixty, which makes writing rather than queueing the more productive response to a bad day.
Questions people ask about flight cancellation and delay
Does the airline owe me money for a four-hour delay in the United States?
Not as a payment for the delay. If the delay is significant and you choose not to travel, the fare comes back. If you fly, the rules give you nothing further, and anything you receive is the airline applying its own policy.
Can the airline give me a voucher instead of a refund?
It can offer one. The refund rule is triggered by your declining the offer, so a voucher only replaces cash if you accept it. Read what you are agreeing to before you tap the button in the app.
What if the flight was cancelled for weather?
For the refund it makes no difference: the fare comes back either way, because the refund is not a penalty on the airline. It matters under the UK regime, which excuses the airline from paying compensation for circumstances outside its control, but the US scheme has no such payment for a weather defence to remove.
Which rules apply to a flight from London to New York?
That depends on the operating airline. A UK or EU carrier is inside the retained UK Regulation in both directions; a US carrier is inside it leaving London and outside it coming back. It is the fact that decides most transatlantic claims, and it is decided before anything else.