What to wear on a cruise, by line and by night

Start with the fact that the lines do not share a vocabulary. Royal Caribbean sorts everything into three named levels. Casual is jeans, polos, sundresses and blouses. Smart Casual is a step up: collared shirts, dresses, skirts and blouses, or pantsuits, with jackets, sports coats and blazers welcome. Formal is branded Dress Your Best, described as a night out in your best black-tie look, and the line publishes how many of those you get: one on a 5-night sailing, two on 6 to 10 nights, three on 11 to 14, and three to four on anything 15 nights or longer, with a note that the count is at the ship's discretion. Celebrity, in the same corporate family, uses two names instead of three. Smart Casual is a dress, skirt, long pants or jeans with a stylish top or button-down, and the line adds the useful clarification that shorts and flip flops do not qualify. Evening Chic is its formal night, one or two per itinerary. Carnival splits the evening into Cruise Casual and Cruise Elegant. Cruise Casual, which is most nights, explicitly includes jeans and even tailored dress shorts with a collared shirt. Cruise Elegant lands once on select short sailings and twice on anything six days or longer, and Carnival is unusually specific about when: on longer cruises the first is the second or third evening of the cruise, and the next is two or three evenings before the end. Princess publishes the most precise count of anyone, as a table running from zero formal evenings on a 1 to 4 day cruise up to a minimum of five on 29 days and longer. Norwegian is the outlier and the reason generic advice fails. It publishes no formal night and no tiers at all, asking only that what you wear feels put-together and suited to the setting.

• Royal Caribbean: Casual, Smart Casual, Formal (Dress Your Best), with a published count by sailing length.
• Celebrity: Smart Casual and Evening Chic, one to two Evening Chic nights per itinerary.
• Carnival: Cruise Casual and Cruise Elegant, one on select short cruises and two on cruises of six days or longer.
• Princess: a published table, from zero formal evenings on a short getaway to five or more on a long voyage.
• Norwegian: no formal night, no tiers, and no requirement to dress up on any night.

Level names, descriptions and formal-night counts were read on royalcaribbean.com, celebritycruises.com, help.carnival.com, princess.com and ncl.com on the dates in the sources below.

The useful question is not what you may wear but what the line has written down that it will not seat you in, and here the lists differ enough to be worth reading. Royal Caribbean's two hard rules apply every night, not just formal night: bare feet are not allowed at any time in any venue, and tank tops are not permitted in the Main Dining Room or specialty dining venues for dinner. Celebrity publishes the longest list, asking guests in the main restaurant to refrain from swimsuits, see-through coverups or robes, bare feet, tank tops, T-shirts and baseball caps. Carnival attaches its list to both evening codes: no ripped or cut-off T-shirts, nothing sheer or see-through, no athletic clothing or gear, and no swimwear, with the same standard applied at the Steakhouse and Rudi's Seagrill. Princess frames it as what is not welcomed in the dining rooms, naming pool or beach attire, gym shorts, ball caps and casual jeans with fraying or holes, and adds that shoes must be worn. Norwegian, which has no formal night to enforce, still asks for shirts and footwear, respectful graphics, and appropriate coverage for a dining environment. Notice the shape of these lists. They are mostly about the pool deck and the gym, not about whether you own a jacket. On a modern ship you can dress well below the formal-night suggestion and still be seated, but you cannot arrive in a wet swimsuit or barefoot. And the escape hatch is published, too: Princess states that even on formal nights you can choose how you dine, with the buffet, casual restaurants and poolside dining open every evening under relaxed dress codes. Every line in this table runs the same arrangement. Formal night is an invitation with a set of dining rooms attached, not a curfew.

• Royal Caribbean: no bare feet in any venue at any time; no tank tops at dinner in the main or specialty dining rooms.
• Celebrity: no swimsuits, see-through coverups or robes, bare feet, tank tops, T-shirts or baseball caps in the main restaurant.
• Carnival: no ripped or cut-off T-shirts, sheer clothing, athletic gear or swimwear, at either evening code.
• Princess: no pool or beach attire, gym shorts, ball caps or frayed jeans in the dining rooms; shoes required.
• Every line keeps a buffet or casual venue open on formal night, so opting out costs you the dining room, not dinner.

Each restriction is quoted from the line named beside it, read on that line's own dress code page on the date in the sources below.

Whatever the itinerary, the single most common packing mistake on a Caribbean sailing is dressing for the Caribbean. Ships are air conditioned to a standard set for a full theatre, a busy dining room and a casino, which means the interior public spaces run cool and stay cool all evening, and they will feel arctic to somebody who has spent the afternoon at 88 degrees on the pool deck. Add the ship's own weather: even a warm sea day produces a steady apparent wind across the open decks, and a balcony at 20 knots after sunset is a different climate from the same balcony at anchor. The lines say this obliquely. Norwegian's guidance is to pack for the destination and that layers will be your best bet, warm or cool. Carnival's daytime list for a warm-weather cruise includes a lightweight sweater, pull-over or jacket right alongside the shorts and swimsuits. Treat both as a hint rather than a suggestion. In practice one packable layer per person covers the theatre, the dining room and the late-night deck, and a second thin layer covers a cold-front morning in port. What actually works is a light cardigan, a linen overshirt or a soft-shell that folds into a day bag, because the layer you leave in the cabin is the layer you spend the evening wishing you had brought two decks down. Also pack for sun in a way that has nothing to do with fashion: a hat that survives wind, sunglasses you can afford to lose over the rail, and a long-sleeve rash guard or light cover for anyone who will be in the water for hours. The sea reflects, the breeze hides the burn, and the second day of a seven-day cruise is a bad time to discover it.

• One packable layer for indoors, always. Theatres and dining rooms are cold on every ship.
• Norwegian's own advice: pack layers, whatever the destination.
• Carnival's own daytime list includes a lightweight sweater, pull-over or jacket for warm-weather cruises.
• A hat that stays on in wind beats a hat that looks better, on an open deck at sea.
• Sun protection that covers skin outperforms reapplying sunscreen you left in the cabin.

The layering advice attributed to Norwegian and the daytime clothing list attributed to Carnival come from those lines' own pages; the air-conditioning and wind observations are ours, not a line's statement.

This is the transition that catches first-time cruisers, and every line writes a rule about it. Royal Caribbean asks that swimwear stays on the Pool Deck, and separately says shorts are welcome for breakfast and lunch, which tells you exactly where the line falls: daytime shorts in the dining room are fine, a wet swimsuit anywhere is not. Carnival's version is the most practical, because it addresses the buffet directly. The Lido Restaurant has a more relaxed dress code than the main dining rooms, but Carnival asks you to respect that the Lido is not the pool area: shirts, bathing suit cover-ups and footwear must always be worn, and you are asked to dry off completely because wet floors are a safety hazard. Norwegian says swimwear should be saved for the pool and extremely short shorts for other activities. Celebrity bans swimsuits and see-through coverups from the main restaurant outright. Princess names pool and beach attire as not welcomed in the dining rooms. Put together, the working rule is simple. A cover-up, a dry shirt and sandals will get you a plate at the buffet on every ship in this table. None of them will get you into the main dining room at dinner. That is what the late-afternoon shower is for, and it is why the cabin's location matters more than people expect on a sea day. Two habits make the change painless. Keep a dry shirt and a pair of sandals in the day bag rather than the cabin, so the walk to lunch does not require a trip down four decks. And on embarkation day, remember that checked luggage typically does not reach the cabin until mid-afternoon, so the outfit you plan to wear at dinner on day one either travels in your carry-on or does not exist yet.

• Royal Caribbean: swimwear stays on the Pool Deck; shorts are welcome at breakfast and lunch.
• Carnival: the Lido requires shirts, cover-ups and footwear, and asks you to dry off completely before entering.
• Celebrity: swimsuits and see-through coverups are not permitted in the main restaurant.
• A cover-up and sandals reach the buffet on any of these ships; they do not reach the main dining room at dinner.
• Day-one dinner clothes belong in the carry-on, since checked bags usually arrive mid-afternoon.

The pool-deck and buffet rules are quoted from Royal Caribbean, Carnival, Celebrity, Norwegian and Princess respectively, each read on that line's own page.

Footwear is the part of cruise packing where the lines give the most concrete guidance and most packing lists give the least. Carnival's daytime list names comfortable rubber-sole flat shoes, sneakers, water shoes or non-slip boat shoes with traction, and notes that select activities and shore excursions may require closed-toe shoes. Norwegian tells you to bring closed-toe comfortable shoes for shore excursions and onboard sports, and is specific that the Ropes Course and the race tracks require closed-toe flat shoes. Royal Caribbean's rule is the blunt one: bare feet are not allowed at any time in any venue. Princess requires shoes in the dining rooms. Two lines go further and ban a category outright, which surprises families every year: Carnival prohibits any footwear with wheels on board, and Princess lists Heely-style shoes among its prohibited items. If your child's favorite shoes have wheels in the heel, they are staying home. The practical minimum for a warm-weather cruise is three pairs. One pair of flip flops or slides that live at the pool and go in a wet bag afterwards. One pair of closed-toe shoes with real tread for excursions, gangways and the ship's sports deck, which also covers the walk through the terminal on embarkation morning with a bag on your shoulder. One pair that works at dinner, which for most people is a sandal that is not a flip flop or a leather shoe that is not a sneaker. Anything beyond that is preference. Two details worth knowing: outdoor decks are washed at night and are genuinely slick before the sun dries them, and tender ports mean stepping between two boats that are moving independently, which is not the moment for a new pair of anything.

• Carnival: rubber-sole flat shoes, sneakers, water shoes or non-slip boat shoes with traction, and closed-toe shoes for some excursions.
• Norwegian: closed-toe flat shoes are required for the Ropes Course and the race tracks.
• Royal Caribbean: bare feet are not allowed at any time in any venue. Princess requires shoes in the dining rooms.
• Wheeled footwear is prohibited on Carnival, and Heely-style shoes are on Princess's prohibited items list.
• Three pairs covers a warm-weather sailing: pool, closed-toe for shore and sport, and one that works at dinner.

Footwear guidance is quoted from Carnival's and Norwegian's own packing pages, Royal Caribbean's dress code page, and the Princess prohibited items list, all read on the dates in the sources.

Two constraints decide how much clothing to bring, and one of them is a rule rather than a preference. The rule: you cannot bring an iron or a garment steamer, on any of these lines. Royal Caribbean's prohibited items list says clothing irons and garment steamers are prohibited with no exceptions. Princess lists clothing irons among items containing a heating element, in the safety hazard section. Norwegian bans items containing any kind of heating element and, on its own packing page, names irons and steamers among the things to leave at home. Carnival prohibits electrical appliances containing a heating element including irons and clothes steamers, and then does something the others do not: it tells you what to use instead, noting that all its ships offer valet laundry for a fee and that most ships, excluding Carnival Firenze, Carnival Luminosa and Carnival Venezia, provide self-service facilities with ironing boards and irons. That reframes the packing problem. Since you cannot press anything in the cabin, choose fabrics that do not need pressing: knits, linen blends that are supposed to look relaxed, and anything that survives being rolled rather than folded. Wrinkle release spray earns its space, and hanging a shirt in the bathroom during a hot shower does most of the rest. The second constraint is arithmetic. Count the formal or elegant nights from the table above and pack that many dressy outfits, not one per night of the cruise. Dinner clothes get worn for three hours in a cold dining room and can repeat. Daytime clothes are the opposite: they get soaked, sunscreened and sweated through, so plan roughly one set per day plus a spare, and take advantage of the fact that a swimsuit dries overnight only if you hang it somewhere with moving air. Two swimsuits per swimmer removes that problem entirely.

• Royal Caribbean, Carnival, Norwegian and Princess all prohibit clothing irons and garment steamers.
• Carnival points guests to valet laundry, and to self-service irons on most ships other than Firenze, Luminosa and Venezia.
• Pack fabrics that tolerate rolling; add wrinkle release spray rather than hoping for an iron.
• Dressy outfits should match the number of formal or elegant nights, not the number of nights.
• Two swimsuits per swimmer, because one never dries overnight in a humid cabin.

The iron and steamer prohibitions are quoted from each line's own prohibited items or packing page, and the self-service laundry detail is Carnival's own wording, including its list of excluded ships.