If you're lucky, Royal Caribbean could send you a free cruise offer in the mail as an incentive to come back onboard and gamble some more.

After you cruise with Royal Caribbean and spend money in the casino, there's a chance you'll be mailed an offer to come back and sail for free or at a discounted rate.
These targeted offers are sent as a post card in the mail, and it's one of the best values right now in cruising.
How it all works can be a bit confusing, so here's a breakdown of how these casino mailers work and what to do if you if you get one.
A card could be mailed to you

Essentially, Royal Caribbean's casino program will send offers to certain members with free or discounted cruises and they are indeed legit.
Unlike scams sent in the mail to get you to attend a timeshare sale presentation, these come directly from Royal Caribbean. They're colorful, and have a special code for redeeming.
Each card has a limited selection of specific sailings. Usually, there are a dozen or so options.

There's no flexibility with the ships or sail dates. You can either pick one or none. There's certainly no obligation.
Depending on your status within Casino Royale and how much you've gambled recently, the cabin selection can vary. You might get offers for an inside or oceanview cabin, or a balcony.
You'll still have to pay the port fees and taxes, which vary depending on which sailing you pick.

The offers could be for any type of cabin category, but most people get an inside or oceanview.
The other factor is if the free cruise covers one or two people.
Sometimes it's just free cruise fare for one person, and you'll have to pay a discounted rate for the second person in the same room. But it could be for two people too. You just have to read the fine print.
Some important information about these casino offers in the mail:
- You still have to pay taxes and all fees, which can be hundreds of dollars
- You earn Crown and Anchor Points from free casino offers
- You can only book 1 sailing with any particular offer code
How do you qualify for free cruise offers from the casino?

No one knows exactly the logic or "casino math" to qualify for random offers, but my experience has taught me consistent play is the key.
The point of these mailers is to entice people that have demonstrated they're willing to gamble in the casino to come back and cruise again so they can gamble more.
Suffice to say, you first need to be go on a Royal Caribbean cruise and play in the casino and wager enough money to "make it" onto the casino's algorithm.

How much you need to wager is anyone's guess, but my best recommendation would be enough to get you 200 - 300 points in the casino on a single sailing.
In my experience, low or no play onboard (especially if you're on a casino comp sailing) can cause your offers to stop or slow down.
Always use your Seapass card to log into the machine before you start playing.
One point is equal to $5 wagered at a slot machine, so to get 300 points, you'd need to wager $1,500. Remember, that's wager and it doesn't matter if you win or lose.
Realistically, you're not going to lose every single bet. But you could certainly have a bad streak of loses and money could go quickly.

The other thing I would recommend doing is ensuring your casino account isn't tied to your kids accounts.
Another unconfirmed theory is if the casino's algorithm notices a minor, it won't send them an offer. So if your account has the same email address as your kids, that could be enough to prevent offers from coming in.
I experienced this problem earlier this year when I was getting no offers at all. At the recommendation of another casino player, I asked the casino host to change my casino account email to different one. That would leave me kids on my old email with Royal Caribbean, but separate me out from them.
Sure enough, a couple of cruises later (with a couple hundred points per sailing in the casino), and my mailbox has been flooded with offers.
To be clear, all of this is a working theory and I can't promise it will work for you. It just seems to represent the best conventional wisdom we have at the moment.
How to book a free cruise with the casino

The card you'll receive will have a list of free cruises. You can choose just one of them, per offer code.
To redeem it, you can do one of three things:
- Call Casino Royale directly and book
- Use Royal Caribbean's new Casino Royale website to redeem it
- Ask your travel agent to do it for you
Not all travel agents will redeem a free casino cruise because Royal Caribbean pays them barely any commission for a free cruise fare.

Calling in is what most people have traditionally done, but the hold times can be lengthy.
The new website appears to be a promising alternative, but it's brand new and a bit of a work in progress. Also, the website has shown offers that don't correlate to what the mailers have and that's been a source of frustration. I'm certain it will get ironed out, but in the meantime, the website may not be totally foolproof.
Don't abuse the offers

A word of warning: only redeem a free cruise offer you will actually go on.
Royal Caribbean changed their policy to penalize people that take advantage of free cruises, but then subsequently miss the cruise.
In past years, casino players would book free casino offers but then no-show to them. It wasn't intentional, but they viewed them as like "maybes" and since the cruise was free, there was no real penalty for missing it.
The cruise line has cracked down on this, and warns you'll lose your $200.00 deposit on the room.
Furthermore, you could be banned from getting free offers in the future if you do it.
Any Recipient who fails to check in at the pier may be suspended from future offers, will forfeit any offer(s) redeemed, and the remaining guests sailing, if any, will be subject to pay the prevailing rates at the time of embarkation.
Basically, if you book the free cruise, make sure you go on it.