The Code: The atmosphere onboard is casual. Most nights are informal, with "resort wear" appropriate. A jacket or shawl, though not required, is recommended.
Number of Formal Nights: There are two gala evenings per Caribbean cruise and one or two per European sailing, depending on length. Suits for men and cocktail dresses for women are recommended.
Nightly Casual Option: For diners wishing for an even more relaxed vibe, a nightly buffet is offered.
Written Restrictions and Jeans: In restaurants, the cruise line asks passengers to not wear beach clothes (shorts, sarongs or flip-flops); shoes are required. Though Costa does not reference jeans directly in its written policy, denim is allowed in the dining room, according to a spokesperson.