There’s no shortage of appealing credit card offers. Virtually every time your turn around, there’s some new card, or an update to an existing one. Card issuers are outdoing themselves in finding ways to get deeper into your wallet.

You’re probably already hip to airline-affiliated credit cards, and you might even have one in your wallet. But cruise lines are in on this game too, offering their own co-branded cards.

Major cruise lines like Holland America, Disney, Norwegian, Princess, Royal Caribbean, Celebrity, and Carnival have rewards credit cards. These cards earn you points that can get you free or discounted cruises, upgrades, cruise line swag, and other goodies. Here’s what you need to know before rushing to fill out an application.

Keep in mind that we’re focusing on the rewards and perks that make these credit cards great options, not things like interest rates and late fees, which can far outweigh the value of any rewards.

When you're working to earn credit card rewards, it's important to practice financial discipline, like paying your balances off in full each month, making payments on time, and not spending more than you can afford to pay back. Basically, treat your credit card like a debit card.

Benefits of co-branded cruise credit cards

Co-branded cruise credit cards offer a variety of perks and rewards, ranging from 0% introductory APR periods to sign-up bonuses in the form of points. Cards co-branded with Celebrity, Royal Caribbean, and Carnival offer 2 points per dollar on purchases with their brands and 1 point per dollar on everything else. Norwegian steps it up with 3x points on Norwegian purchases.

Read more: The best current credit card sign-up bonuses

Carnival's World Mastercard has a perk that is rare in the credit card landscape. You can earn 1 point per dollar for balance transfers made within the first 30 days, up to 5,000 points. What makes this special? Almost no credit cards offer rewards on a balance transfer. Doing the math, 5,000 points is worth $50 (when valued at 1 cent per point), and you'll pay a 3% balance transfer fee. If you transfer $5,000, for example, you'll pay a $150 balance transfer fee and earn $50 in points.

Read more: The best balance transfer credit cards

Cruise line co-branded cards are most rewarding for consumers who prefer taking cruises over any other type of travel. You generally earn the highest rewards rate for cruise purchases. These cards often offer a sign-up bonus you can use to offset the cost of a cruise, along with rewards you can redeem to lower the cost even further. If the card allows you to redeem points for other vacation expenses like hotels and rental cars, it can allow you to take a vacation on land for a lower price, too.

For Russ Nauta, owner of CreditCardReviews.com, signing up for the Disney Premier Visa Card was a smart move. "I have three children, so we are big Disney fans. Although there is a $49 annual fee, users can get a lot out of the card such as 0% APR for the first six months on certain Disney vacation packages (including cruises!). Then you get some nice additional benefits such as a $200 statement credit after spending just $500 in the first three months; after that 1-2% Disney Rewards Dollars on purchases. For a family that goes to Disney even every few years, this is a great deal."

The cons

While co-branded cruise line credit cards have some perks tailor-made for cruisers, there are some key considerations. As always, look at the fine print. What are the annual fees, the interest rates, policy on late fees and more? How do they compare with other cards? Do your research.

Be sure you understand how these cards work. Don't think that if you spend more on your credit card you'll move up in status like Platinum or Gold with the cruise line's loyalty program. The big benefit is that you could get a free cruise if you earn enough points, but this doesn't mean you should spend more than you were planning to already just to get a trip - in that case, you're paying more than the rewards are worth.

Also, take note of when points expire. There's typically a five-year time window from when you earn them to expiration.

Consider alternatives

Other credit cards may be better suited for you and your lifestyle. "Unless you take cruises very frequently, a general travel rewards card that can help you earn points on your cruises and also help pay for cruises when you spend on other travel such as airfare may be a better choice," says Greg Mahnken, an analyst with Credit Card Insider.

General travel rewards cards typically offer a slew of other benefits ranging from rental car insurance to trip interruption and cancellation insurance which may be of additional value to you in your travels.

Furthermore, Sara Rathner, a credit card expert with NerdWallet, says general travel cards give you maximum flexibility when you redeem rewards. She offers examples: "The American Express Platinum offers a statement credit and other perks when you book your cruise through Amex. With the Chase Sapphire Reserve, you get a $300 annual travel statement credit that can be applied to booking a cruise, plus your Chase Ultimate Rewards points are worth 50% more when redeemed for travel, including cruises. While these premium cards charge high annual fees, you can offset the cost by taking full advantage of valuable card benefits like statement credits."

Click here to learn more about the Amex Platinum card.

Click here to learn more about the Chase Sapphire Reserve.

Marshall Armond, CEO of CreditRevo.com, also believes there are better rewards cards that can be utilized to redeem towards the price of the cruise: "The Capital One® Venture® Rewards Credit Card offers a 50,000-mile bonus after you spend $3,000 in the first three months. So if sign up for that credit card you book cruise that cost you $3,500, you will get bonus points equal to $500, that you can use to offset the price of the cruise. That same purchase, if done on a Norwegian Cruise Line and their credit card, would only yield you enough points for about a $110 discount or onboard credits."

Click here to learn more about the Capital One Venture card.