Princess cruise lines has a strict alcohol policy: Passengers under 21 years are not allowed to buy or consume alcohol on board. Duty-free alcohol can be purchased, but will only be delivered to you on the last day of your cruise.
Also, if you buy alcohol at any of the ports or embarkations, you are not allowed to consume it on board. You have to hand it over at the gangway and it will be delivered to you on the last day of your journey.
However, it's possible to bring wine or champagne on board to celebrate special occasions. If you want to consume it in of the dining rooms or restaurants, you have to pay a $15 corkage fee
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