What is the 24-hour rule Lufthansa? Lufthansa offers a 24-hour rule, allowing you to change or cancel your flight booking within 24 hours of making it, without incurring any additional fees. To make the changes over the phone hassle-free, simply call 1-877-300-7101 and 1-866-463-2404. Lufthansa's 24-hour rule is a crucial policy for travelers, offering flexibility and peace of mind. It allows passengers to make changes or cancel their flights free of charge within 24 hours of booking. This rule is particularly beneficial for those who need to adjust their travel plans suddenly or have made an error while booking their flight.