Infants must be at least 6 months of age at the time of embarkation in order to sail. Children must be at least 12 months of age at the time of embarkation to sail on trans-ocean crossings and remote itineraries, where there are more than 2 consecutive sea days.

For most major cruise lines in 2026, the absolute youngest age for an infant to sail is 6 months old on the day of embarkation. This policy is strictly enforced by lines like Royal Caribbean, Carnival, and Norwegian due to the limited pediatric medical facilities available on board. However, for specific itineraries that involve "higher risk" or more consecutive days at sea—such as Transatlantic, Transpacific, Hawaii, or World Cruises—the minimum age typically increases to 12 months. These rules exist because cruise ship medical centers are designed for stabilizing adults and are not equipped to handle neonatal emergencies or provide specialized pediatric intensive care. If you attempt to board with an infant younger than the required age, you will be denied boarding without a refund. Additionally, parents should note that children must be fully potty-trained to use most onboard pools (swim diapers are generally banned in main pools), which often makes "age 3" a more practical milestone for families wanting the full cruise experience.