Getting on a cruise ship takes a lot more effort than checking into a hotel: You have to go through security, have your passport checked, and check in at multiple stations.
People taking a cruise are, of course, really eager to get on board because the sooner you board, the sooner you can get something to eat, have your first drink or visit a pool.
Ships generally have a number of bars and restaurants open as soon as they start letting people board, which can be as early as 11 a.m. Boarding passengers have selected windows during which they're supposed to get on the ship.
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It varies by cruise line, but in some cases you can buy your way into the earliest boarding groups, while suite passengers on both Royal Caribbean (RCL) and Carnival get priority.
It's also possible, however, to get an early boarding time without spending any extra money, simply by checking in at the earliest possible date and selecting an early time.
If you board early, there's a catch: Your room won't be ready, and depending on whether you checked your luggage, you will have your carry-on bags with you and your luggage if you opted to walk it on yourself.
All cruise lines have slightly different rules for handling that luggage before rooms are opened to passengers (usually about 1:30 p.m. on Royal Caribbean and Carnival Cruise Line (CCL) ships).
Cruise-line baggage and room rules vary
Having a bag with you is an added burden and most people are eager to get their bags to their cabin. It's hard to fully enjoy yourself on a cruise ship when you're lugging around even a carry-on bag because that bag contains your passport and maybe a laptop as well as any medicine you might need.
Royal Caribbean does not allow nonsuite passengers to access their rooms until they are fully ready. People who buy the cruise line's The Key pass, which enables early access, can leave their bags at a designated spot on the ship for quick delivery to their rooms.
All other passengers must wait until the captain announces that the rooms are ready before making their way to their rooms. Once that happens, they can fully use their rooms, unpack, take a nap, or do whatever else they might like.
Royal Caribbean's Celebrity Cruises brand has a very different policy. All passengers are allowed to visit their cabins to drop off their bags. They are supposed to do that, then leave so the final cleaning can be done.
Carnival's namesake cruise line has a policy that falls somewhere between the two. The company's brand ambassador, John Heald, wants to make its policy very clear.
Carnival issues a plea to passengers
Carnival allows some, but not all, passengers to drop off their bags in their cabins before they have been opened. The cruise line allows people who have hit certain levels in its loyalty programs as well as suite passengers, and people who paid for its early boarding program, "Faster to the Fun," to drop their bags off in the cabin.
"Here is my almost monthly reminder to my friends, who are diamond, platinum, staying in a suite, or have Faster to the Fun," Heald wrote. "You can go directly to your cabin to drop off your carry-on bags." Once they've done that, Heald asks that those passengers leave their rooms so they can be fully and properly cleaned.
The cruise line wants passengers who have reached those levels, or paid for more expensive rooms, to have this added convenience, but it doesn't want passengers interfering with the cleaning process.
"I’ve been dealing with five different guests who have all had some kind of confrontation with the crew regarding this," Heald added. "Some have tried to have a shower, some have tried to unpack, and one gentleman literally decided to show his loyalty card very close up to the housekeeping staff demanding she leave the cabin, which was yet to be prepared because 'he needed to take a nap."