If you are considered a “young adult” (meaning 18-20 years old) and you are sailing with a parent who signs a waiver, then you can drink wine and beer aboard the ship — but not cocktails. Passengers must be 21 years of age or older to purchase or consume alcohol.

For travelers aged 18 to 20, the ability to legally consume alcohol on a cruise depends entirely on the ship's itinerary and the "origin" of the sailing. On cruises departing from the United States or the Caribbean, the drinking age is strictly 21, and there is generally no legal way around this. However, many major lines like Royal Caribbean, MSC, and Norwegian Cruise Line lower the minimum age to 18 for sailings that originate in Europe, South America, Australia, or Asia. Additionally, on some lines in international waters, a parent or legal guardian traveling with a young adult (18–20) can sign a "Young Adult Alcoholic Beverage Waiver" that allows the minor to purchase and consume beer and wine. It is important to note that attempting to use a fake ID or having an older passenger "smuggle" drinks to you is a violation of the ship's Guest Conduct Policy and can lead to immediate disembarkation at the next port without a refund.