A sea day is a day spent in transit on your cruise while the ship is sailing to its next destination. Without a port stop, these days are typically marked with extra programming and dining to accommodate all passengers onboard.
Activities and entertainment tend to ramp up on days at sea because everyone is onboard the ship. You might notice more trivia contests, tournaments in the casino, afternoon shows in the theater, musical entertainment, poolside activities and even special classes not offered on other days of your cruise. The cruise director and activity coordinators work hard to make sure no one is bored, even in the middle of the ocean.
Even if your ship is a big and busy one, consider bringing your own things to do as backup -- music to listen to while you relax, books and tablet games to keep you busy, etc.
Breakfast, lunch and dinner are always served at the buffet and usually one (or more) of the main dining rooms every day, but sea days afford you the opportunity to explore those options fully without the rush of getting ready for excursions. Plus, on sea days, some specialty venues may open for breakfast or lunch, as well.
Watch your daily cruise planner closely for special sea day brunches, afternoon teas, pool party-style dinners and even menu items (hint: lobster roll at Ocean Blue on the Waterfront onboard select Norwegian Cruise Line ships) that are available only on sea days.
But don't put all your faith in the planner; you may occasionally encounter unadvertised sea day food specials simply by walking round the ship. Examples might include fresh peel-and-eat shrimp on the buffet, coffee bar specials or even an impromptu outdoor cooking station in nice weather.
Also, be aware that all restaurant hours might change slightly during these days, including later breakfast hours to accommodate late sleepers. Be sure to check your daily cruise bulletin for changes.
A full day onboard your cruise ship gives you time to explore everything on offer. If you spent the previous day rushing around in port, a sea day allows you to sit back and soak in ship life, whether it's a leisurely brunch, a full spa day or napping in the sun by the pool. In addition, you get the full experience of sailing at sea -- watching the waves or the shoreside scenery, looking for marine life and feeling the gentle rocking of the ship.
If you love activity, you have an entire day to try out the ship's water slides, rock climbing walls and other top-deck attractions, or fill your time with wine tastings, Ping-Pong tournaments, movies or special lectures.
Finally, cruises with a wealth of sea days (such as ocean crossings) may also be more discounted than cruises with one port right after another.
While more activities are featured on sea days, if those events are not to your liking, the day(s) can feel pretty long. Plus, because everyone is onboard, certain public areas like the pool, the lido deck and buffet area might be crowded and deck chairs in high demand.
Reservations for alternative restaurants, limited-space attractions (like escape rooms or laser tag) and shows can also be a challenge on sea days, so plan to book those in advance. And with high demand for spa services on sea days, there are rarely discounts offered at the spa and fitness center.
Depending on your itinerary and the length of your cruise, you may have just one sea day in transit or multiple (as is the case with ocean crossings). Study your itinerary before you sail so you know how many sea days to expect and whether they're broken up with ports or all in a row. It's also important to know that weather or other port conditions can force unexpected sea days.
The What to Expect on a Cruise series, written by Cruise Critic's editorial staff, is a resource guide, where we answer the most common questions about cruise ship life -- including cruise food, cabins, drinks and onboard fun -- as well as money matters before and during your cruise and visiting ports of call on your cruise.
Updated February 27, 2020