You do not have to "buy" water on a cruise, as safe, potable tap water is provided for free in all staterooms and at various self-service stations. In 2026, most ships feature "Hydration Stations" in the buffet and lido areas where you can fill a glass or refill a bottle with chilled, filtered water. However, if you prefer bottled water, you will typically need to pay for it individually or have it included in a beverage package. Many cruise lines, such as Carnival and NCL, strictly prohibit guests from bringing their own cases of bottled water on board to streamline security, though they may allow a small number of cans. To save money, many seasoned cruisers bring an insulated reusable water bottle (like a Yeti or Hydro Flask) and fill it up for free on the ship, ensuring they stay hydrated at the pool or during shore excursions without paying the $4–$6 premium for single-use plastic bottles.