How does boarding work on Royal Caribbean and Carnival cruises?

A cruise ship is docked at a pier. Carnival lead DBK

Boarding a cruise ship can be stressful.

Hundreds, maybe thousands, of people all are trying to get to the same place, and the process has some quirks that aren't like checking into a hotel. The process is fairly similar to boarding an international flight, with the added problem of having many more passengers than any plane carries.

You can, however, make the process easier if you know what to expect and do everything you can before you board.

First, it's important to do three things before your cruise, and those are the same across Carnival, Royal Caribbean and Celebrity Cruises:

• Check in as soon as you can: Each cruise line's app will share the date when check-in opens. Put it on your calendar since checking in early will give you your pick of times to board.
• Have your travel documents ready: It's easiest to travel with a passport, but most sailings from U.S. ports allow you to travel with a license and an original birth certificate.
• Fill out the health form: 24 hours before your cruise, a brief health form will be available to fill out.

After that, here's what will happen on embarkation day — the day your cruise leaves — before you get on the ship.

Sign up for the Come Cruise With Me newsletter to save money on your next (or your first) cruise.

Royal Caribbean, Carnival and Celebrity use a similar embarkation process

Whether you are being dropped off at the cruise port or you plan to park there, it's important to know which terminal you are sailing from.

Both Royal Caribbean and Celebrity share that information with you in various emails and cruise documents. It will also be shown on digital boards as you enter the port, but it's best to know beforehand as those boards have been known to not always be operational.

In general, you should aim to arrive a bit before your allotted boarding time, which you selected when you checked in. If you arrive early, you run the risk of having to stay outside in the sun until your time comes.

Royal Caribbean offers flexible priority boarding only to suite (not junior suite) customers and Pinnacle members of its Crown & Anchor loyalty program. (This is the top level of the program.) It also sells a pass called the Key, which offers priority boarding, an embarkation day lunch, internet access and some other perks.

Celebrity offers flexible boarding to people who pay for its VIP Pass, an offering similar to the Key. The cruise line does not have a dedicated boarding line for suite passengers in all ports, but it says this on its website:

Boarding times (Embarkation) will vary according to port, itinerary, and/or ship, and may even vary by sail date due to operational situations like Coast Guard drills, etc. Guests who have completed the on-line check in, are member of our Loyalty programs, or who are reserved in Suites or Concierge Class (Celebrity) may use priority embarkation lines at the pier terminal, where available.

Carnival sells a product called Faster to the Fun, which enables passengers to board early, and it offers priority check-in for select passengers.

"Carnival’s Priority Check-in is an exclusive service designed to afford our VIFP Diamond, Platinum, and deluxe suite guests with special embarkation and debarkation privileges on cruises from the U.S. and Europe," the cruise line explains on its website.

Want the latest cruise news and deals? Sign up for the Come Cruise With Me newsletter.

What happens in a cruise check-in line?

When you prepare to join the line to board the ship, have your cruise ticket and your passport or alternate travel documents readily available. Generally, your cruise ticket will be glanced at by a worker as you enter the building.

After that, all guests will go through a metal detector. The cruise lines will be scanning for contraband like weapons, alcohol, irons and other prohibited items.

Once you pass that check, you will be directed to a line where a terminal worker will scan your passport or check your alternate documents, and check your cruise ticket.

The worker may also take a quick photo if you did not do that as part of the check-in process or if they don't think your photo meets the requirements.

You will then pass through security before having to show your ticket/boarding pass one more time and boarding the ship.

Once you board, Carnival, Celebrity and Royal Caribbean all use a virtual muster drill. You can opt to watch the safety videos on your phone and then check in at your station, or you can report to your station, see a safety demo, and then be checked in.

Muster drills are mandatory and it's best to take care of it as soon as you get on board so you can then focus on starting your vacation.