On Royal Caribbean, the "Kids Sail Free" promotion typically applies to children who are 12 years old and younger at the time of the sailing's departure date. This offer generally allows the third and fourth guests in a stateroom to sail for $0 cruise fare, provided they meet the age requirement and are staying in the same cabin as two full-fare-paying passengers. It is important to note that even when the cruise fare is free, parents must still pay for the child's taxes, port fees, and gratuities, which can sometimes add several hundred dollars to the total cost. Furthermore, Royal Caribbean frequently implements "blackout dates" during major holidays and school breaks—such as Spring Break, Thanksgiving, and Christmas—where the promotion does not apply. In 2026, many families use this deal to make luxury family vacations more affordable, but savvy travelers always check the specific terms and conditions for their chosen ship and itinerary to ensure their travel dates align with the active promotional window.