Turning 50 can be traumatic for some, but mid-lifers have long comforted themselves with an upside: Finally, they can get an AARP card and reap big travel savings. Indeed, the advocacy organization for older Americans does provide cruise discounts, among other travel deals. But before you pack your bags, first some perspective: No one's giving away free cruises.

AARP membership runs $16 per year, with price breaks for a multiyear commitment. Here's how cruisers can make the most out of a membership.

AARP Cruise Deals

Because AARP members represent a sizable market, accounting for more than 20 percent of all U.S.-based cruise passengers, cruise companies have incentive to provide discounts to lure travelers onboard. Plus -- and this is a little-known fact -- the group now welcomes members at any age, so travelers younger than 50 can sign up and benefit from member discounts.

Members should first head to the AARPAdvantages website, which will list current promotions and provide links for booking.

A few cruise lines and tour companies offer AARP cruise deals on every sailing. Recently, Grand European Travel was giving members a $100 per person discount on Uniworld river cruises. Collette, which runs European river cruises, was offering $50 off per person.

However, most AARP cruise discounts are tied to specific sailings. They must be booked through the AARP Travel Center Powered by Expedia.

You'll find most major lines represented, including Carnival, Celebrity, Holland America, Norwegian, Royal Caribbean, MSC, Disney and Princess. A typical offer might be a range of onboard credit, with the amount varying by how much you spend on the cruise.

While there's no simple way to see all the current discounts, once you start searching, the booking engine does a good job showing which trips have promotions. Keep in mind, cruise prices and specials aren't necessarily more generous than what you can find elsewhere. Travelers should compare AARP cruise discounts with deals offered elsewhere through travel agents, online booking engines and cruise companies themselves to make sure they're getting the best value.

Also, the organization's promotions are generally capacity controlled. You're most likely to find a bargain if a cruise isn't selling well and for last-minute bookings on ships with extra cabins.

Other AARP Discounts Useful to Cruisers

Cruise travelers should also consider AARP for deals on the other travel portions of their cruise vacations, such as airfare to an overseas homeport or a pre-cruise hotel stay. AARP members traveling to Europe for a sailing can get a discount of $200 on British Airways business class flights, and $65 for economy, as long as they're flying round trip to and from the same destination. The organization also offers a wide range of discounts with hotel chains, which can help with lodging before or after a cruise.

Liberty Travel Partnership

AARP also has a partnership with Liberty Travel, a national travel company, and offers discounts for members. Members can access Liberty Travel through its AARP site.

The AARP cruise promotions are limited, with deals offered only on certain trips. For example, at press time, Liberty Travel featured deals on Holland America in Alaska, and Norwegian in Hawaii, where in addition to a small discount, you could get a free pre-cruise hotel room, prepaid service charges or a shore excursion credit. The company also reduces trip deposits required from AARP members.

Discounted Cruise Gift Cards

Another way to get a price break is with an AARP cruise line gift-card promotion that will provide a 10 percent discount on gift cards for Carnival Cruise Lines and occasionally for other major lines like Royal Caribbean. In theory, members must take quizzes to earn points, which will allow them to buy the cards, but the requirements are minimal. You can earn points just for logging into the website and buying cards. (Note, this does not refer to the non-travel gift cards offered through the main AARP site.)

To participate, go to the Rewards for Good program on the AARP website, where you'll be asked to sign up for the program. You don't have to be an AARP member to participate.

Inventory varies, but every few weeks you can usually find $100 and $500 Carnival cards at a 10 percent discount. Usually there's a posting on Cruise Critic's Carnival discussion board noting the availability. It pays to act fast because they will sell out. You can use these cards to buy a cruise or for expenses on board.

Often the cards can be emailed, but if you're buying physical cards worth $500 or more, someone will have to be home to sign for the delivery.

Other Senior Cruise Discounts

Finally, it's worth noting that, apart from AARP, some cruise lines offer upgrades and other deals on select cruises to older travelers, usually 55 and up. You do not need to be part of an organization for seniors.

Carnival lists its discounted senior cruises on its website. Other lines, including Celebrity and Royal Caribbean, offer an option to search for senior-discounted trips on their main search engines.