A new measure signed into law last month in the United States will force airlines to refund baggage fees for delayed bags. Specifically, the law says airlines will be required to “promptly provide to a passenger an automated refund for any ancillary fees paid by the passenger for checked baggage” if a checked bag isn’t delivered to the passenger within 12 hours of arrival for a domestic flight or within 15 for an international flight. To get the refund, passengers need to notify the airline of the lost or delayed baggage. The goal is to make sure “passengers won’t have to spend a ton of time tracking down a refund when the airline doesn’t deliver,” said U.S. Sen. John Thune, chairman of the Senate Commerce committee, during remarks on the Senate floor in August. To get the refund, you’ll have to notify the airline of the lost or delayed baggage. The measure is included as part of a Federal Aviation Administration re-authorization extension bill that President Barack Obama signed into law last month. The bill instructs the U.S. Transportation Secretary to develop regulations on the issue within one year.