Dress on cruises is casual by day, shorts and T-shirts are acceptable ( if tasteful ) even in the dining room.  Dinner usually has a dress code that varies daily.

Casual :  slacks with a sports coat for men (No Jeans ) slacks and a blouse , sundresses or pantsuit for women.

Informal : Jackets with or without a tie for men, Dress or pantsuits for women

Formal: Dark suit for men, evening gown or cocktail dress for women

Three or four day cruises have one formal night , Seven day cruises have two formal nights and most ten day cruises have three formal nights.  Basically the longer and more expensive the cruise is ( per day ) the more formal nights there will be. Keep in mind however that dark suits and ties are acceptable on even the most exclusive cruise ships.

With more and more cruise lines becoming family oriented, check with your cruise line or travel agent/agency for ship guidelines.

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