Many cruisers dream of scoring an upgrade on their upcoming voyage. Who wouldn't want a better cabin for less?
Unfortunately, there's no way to guarantee an upgrade. For example, you could be on a fully booked sailing, which would squash your chance of receiving an upgrade to an ocean-view balcony stateroom.
However, some strategies may increase your chances of scoring that coveted cabin upgrade.
Pay for a better stateroom through an exclusive offer

Sometimes, you may get a special email offer allowing you to pay to upgrade to a higher cabin category than originally booked.
These offers come at a discount compared to initially booking the room. While there are countless ways to customize your cruise experience, from specialty restaurants to shore excursions, a larger stateroom with natural light is a must-have for many.
It's worth keeping an eye on your email inbox, as these offers can be sent out months in advance and are subject to availability. If you don't act quick enough, it might expire before you head to confirm the upgrade!
Read more: 8 signs you're ready to move up from a cruise ship balcony to a suite
Bid on a cruise ship cabin upgrade

Certain cruise lines, including Celebrity and Royal Caribbean, have upgrade programs that let confirmed guests bid on a stateroom upgrade. If your bid is chosen, you will automatically be billed and upgraded to the higher cabin category for your cruise.
You can check to see if your booking is eligible for the bidding program about one month before your cruise. Typically, you will need your last name and reservation number handy to access the portal with the available categories and minimum bids.
Not every bid is accepted, though. Even if you place what you think is a compelling offer, someone else may have placed a higher bid. There's no way to tell what other cruisers may have placed, even if the cruise line's bid rating system says you're making a strong offer.
Read more: Celebrity MoveUp: How to win a cruise ship cabin upgrade bid
Hope for the best with a guaranteed fare

Guarantee (GTY) fares are typically the cheapest rates for any given stateroom category. Instead of choosing your exact room, the cruise line will randomly assign your cabin closer to your sail date. They're ideal for cruisers who aren't bothered by their stateroom's location and want to save money on their cruise fare.
You won't be assigned a cabin in a lower cabin. So, for instance, if you reserved an ocean-view GTY stateroom, you won't be given a windowless interior cabin. However, this opens up the possibility of receiving a stateroom in a higher category. In fact, this happened to two Cruise.Blog readers, Jackie and Joe, who booked an inside cabin on MSC Seashore only to receive a balcony stateroom upon checking in for their 4-night cruise.
Similarly, Cruise.Blog's video editor Jenna was also assigned a balcony cabin on her weeklong Mediterranean cruise on Costa Toscana, even though she only paid for an interior stateroom.

Receiving an upgrade is never a guarantee, though. More often than not, you will be assigned a stateroom in your chosen category, whether that's an inside, ocean view, or balcony cabin. However, to increase your odds, try sailing during the off-season.
Cruises during cruising periods, like spring break, summer, and the winter holidays, tend to be sold out.
Read more: Unsold cruise cabins: How to find deals when ships aren’t full
Book during a special promotion

Cruise lines offer deals throughout the year, which can sometimes include discounted upgrades or other perks. For example, Princess Cruises' website may advertise free room upgrades. Though it sounds great, just read the terms and conditions before getting too excited.
Sometimes, the "upgrade" only applies to like-to-like stateroom types (i.e., interior to interior or balcony to balcony). Moreover, luxury suites, such as the Sanctuary Collection, may be excluded.
The "upgrade" may come with restrictions, too. For instance, it might require you to book a higher category in the first place, rather than banking on an upgrade from an inside cabin to a balcony.
Read more: Best rooms on a cruise ship: Deck, location, & category
Reasons to decline an upgrade on a cruise ship

While the thought of staying in a nicer cruise cabin might be enticing, it isn't always the right move. For example, upgrades are rarely free.
Typically, you must pay to confirm an upgrade before sailing, which could set you back hundreds of dollars. Though the price to upgrade is less than typically booking the higher category cabin outright, that's money that can be allocated toward other add-ons, including drink packages or shore excursions. Additionally, if you upgrade to a suite, you'll be responsible for the higher daily gratuity amount.
While the upgrade fee is usually less than booking the higher-category cabin outright, that extra money could be spent on other add-ons, such as drink packages or shore excursions, or pre-cruise flights.

Another reason you may want to think twice about cruise cabin upgrades is that you won't have any control over the location.
If you are someone who easily gets motion sick, a forward cabin isn't ideal, as it's more prone to the ship’s movement. You might also end up with a cabin in a location that isn’t as convenient for you, such as a noisy area near the ship's late-night club.
Alternatively, if you have split your party between two rooms, there's no way to guarantee that both rooms will receive an upgrade. Even if one does, the new stateroom may be located on the other side of the ship or on a different deck, which may be inconvenient for families with younger kids who don't want to be separated.