What is the DOT 3-hour delay rule?

The "3-hour rule" actually refers to two separate federal regulations that both use the 3-hour threshold:

1. The tarmac delay rule (14 CFR 259.4): Airlines must offer passengers the chance to deplane after 3 hours sitting on the tarmac for domestic flights (4 hours international). Airlines that violate this face fines up to $27,500 per passenger. Food and water must be provided within 2 hours.

2. The significant delay refund rule (2026): A domestic flight delayed 3+ hours (6+ hours international) from its original departure time is considered a "significant change." This entitles you to a full cash refund — not a voucher, not credit, cash — if you choose not to travel. The airline must process this within 7 business days for credit cards and 20 days for cash/check.

These are separate rights, and both can apply to the same situation. If you're sitting on the tarmac for 3+ hours AND your total delay exceeds 3 hours, you can invoke both rules.

The practical difference: the tarmac rule is about getting off the plane. The refund rule is about getting your money back. Most passengers don't realize they have both options, and airlines aren't rushing to explain.