Yes, jeans are allowed on Princess Cruises, but there are specific rules about where and when you can wear them. On "Smart Casual" nights, which make up the majority of the cruise, clean and neat jeans without holes or fraying are perfectly acceptable in the main dining rooms and specialty restaurants. However, Princess Cruises officially states that "casual jeans with fraying and/or holes" are not welcomed in the dining rooms at dinner. On "Formal Nights," the dress code shifts significantly; while many men wear tuxedos or dark suits and women wear evening gowns, some guests opt for "dressy" jeans paired with a blazer, though this is technically below the suggested "Formal" standard. During the day, jeans are welcome everywhere on the ship, including all dining venues. If you prefer to stay casual even on formal nights, the World Fresh Marketplace (buffet) always allows jeans and casual attire. Ultimately, as long as your denim is in good condition and not "distressed," you will be comfortably within the dress code for most of your voyage.