Sadly, yes you can. Just like the airlines, cruise lines will oversell their cabins knowing that a certain percentage won’t make the sailing for one reason or another. They may also need to take the ship in for repairs, or get an offer to book the entire ship on a charter or the ship may be getting redeployed to a new port. Whatever the reason, in the contract you agreed to when you booked the cruise will be a clause giving the cruise line the right to cancel or modify your cruise as they see fit. For example, in the Disney contract you will find:
Disney Cruise Line may in its sole discretion and without prior notice change, substitute, postpone, cancel or deviate from any scheduled sailing, itinerary or call at any port, and may substitute another vessel for the ship, and shall not be liable for any loss or damage incurred by a Guest as a result of any such change, substitution, postponement, cancellation or deviation.
I’m not picking on Disney, you’ll find that sort of language in every cruise line’s contract.
So, what do you do if you do get bumped? And it is a very rare occurrence. First off, calm down. You aren’t the first or likely the last person that agent will be dealing with and both of you are feeling stressed. If you can stay calm and pleasant, you’re better positioned to come out ahead. Listen to what they offer in compensation. Odds are it will be either a refund of your cruise fee or a re-booking on a similar cruise (same ship-different date or similar itinerary on another ship). Two things to immediately ask for are coverage of your non-refundable costs (hotel deposits, airfare cancellation fees, rental car fees, etc.) and an onboard credit for your troubles. As long as your request is pleasant and reasonable, you’re likely to get it.
Sometimes, it is a particular class of cabin that is overbooked. If so, ask for a free upgrade to another class. More likely, they’ll try to get you to pay an upgrade fee but remind them that if you aren’t in it, that cabin may go unsold. Especially if its very close to sailing date. Again, be reasonable and don’t expect a free upgrade from inside to a spa suite, but the upgrade fee might be less than you would have ever paid for that spa…
The other thing is have travel insurance! However, check that carefully as well. For example, the “Cancel for any reason” policy with Travel Guard.still only covers about 50-75% of other expenses. The cruise line may be much more amenable to picking up the other half without arguing. And if they’re only paying a small part, they might be happy to toss in a few perks like some champagne… Hey, it never hurts to ask, but as Grandma always said, “you catch more flies with honey than with vinegar.”