Bartender in an airplane
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A good travel rewards credit card is indispensable if you love to travel. As the summer vacation season kicks in, families with kids out of school, college students, retirees and others who enjoy adventuring to different places will be looking to earn points, airline miles and rewards.

Your travel and spending habits will help you determine which credit card is best.

“If you’re looking more to get free hotels, you may want to consider credit cards that are hotel-branded,” says Patti Geroulis, founder of the blog site The Travel Sisters. “If you’re open to both miles and hotels, you might look at a credit card that offers more flexible rewards points.”

Look for the following features and secret perks before you choose a travel rewards card.

1. Rewards

Frequent flyers will want to take advantage of a credit card that rewards them for all that travel.

The better cards allow you to earn “2 or 3 points for your dollar” on bonus categories, such as airfare, hotel stays and restaurants, Geroulis says.

Some co-branded cards may let you earn up to 5 points per dollar on purchases at the airline or hotel partner, but the big bonus may be worthwhile only for repeat customers. A good travel credit card should offer rewards on other purchases, too.

“You should be getting at least 1 mile per dollar, and it should be a program you actually value,” says Scott Mackenzie, a Dell marketing adviser who founded a travel blog site called Travel Codex.

Beyond a base rewards program, look for a sign-up bonus, such as extra points or miles for spending a certain amount of money with the card within a specified time frame.

“One bonus can be enough for one or two flights or more,” Geroulis says. “Keep an eye out and sign up for the credit when (the offer) is … higher than normal.”

2. Big bells and whistles

Be sure to look for additional features “that make your travel a lot more comfortable,” says Beverly Harzog, independent credit card expert and author of “The Debt Escape Plan: How to Free Yourself From Credit Card Balances, Boost Your Credit Score and Live Debt-Free.”

“That’s very important on these cards.”

Some co-branded airline credit cards, for instance, give cardholders free access to that carrier’s airport clubs or lounges. They also entitle you to flight or hotel upgrades, early boarding options and free amenities such as Wi-Fi or continental breakfasts.

The most elite travel cards feature concierge services and access to exclusive events. Some may offer private car service or even jet rentals. Shop around to find a card that features the particular perks you want.

“It kind of depends on how you use your credit card and what’s the most important value to you,” says travel expert Ed Perkins, who writes for  SmarterTravel.com.

3. Fee waivers

Frequent flyers will want a credit card that doesn’t charge foreign transaction fees, which are the issuer’s charges for handling a transaction outside the U.S. These fees run between 1 and 3 percent per transaction.

“Coming back from a trip and finding out you’ve been dinged 3 percent for every purchase is just annoying,” Mackenzie says.

With an airline-branded credit card, you also may be able to avoid extra airline charges, such as baggage fees or “close-in booking fees,” which are imposed if you book a flight close to your departure date using your rewards.

Frequent flyers who can avoid those fees shouldn’t balk if their travel rewards card comes with an annual fee.

“The basic cards generally have an annual fee between $80 and $100,” Perkins says. If you pay $25 each way to check a bag, you’ll recoup that annual fee in a couple of round trips.

4. Insurance coverage

Some cards provide trip cancellation insurance, which reimburses you if your vacation gets canceled and the costs are otherwise nonrefundable. Other cards will cover the cost of lost or delayed baggage by paying you up to a certain amount to buy items you need on your trip.

Many cards also provide additional rental car insurance, which “can save you $15 to $20 (a day) versus buying it at the car rental lot,” Mackenzie says. This insurance typically offers some collision and theft protection.

Of course, you’ll have to charge the associated travel expenses to your travel rewards credit card in order to reap a particular benefit.

Something to note: The terms and conditions of insurance perks will vary and come with restrictions. For example, most trip cancellation insurance applies only in cases of death, injury or serious illness.

“It’s a rare occurrence that you would actually use (it),” says Mackenzie. However, these ancillary benefits can still help you choose between two similar cards.

5. Flexibility

All these rewards will be essentially worthless if you have to jump through hoops to earn them. Read your card’s terms and conditions to make sure the rewards aren’t subject to blackout dates.

“You want to be able to get a flight when it’s convenient to you and when you want to travel, not when it’s convenient for the airline,” Harzog says.

You also don’t want to lose points or miles due to inactivity or issuer-imposed expiration dates. Look for a card that lets you transfer rewards to a variety of hotel or airline partners.

That way, you can pool miles with points earned through an affiliated resort’s loyalty program and redeem rewards more quickly. You’ll also increase your odds of snagging a deal on airfare or accommodations.

“In general, flexible rewards points are really good,” Geroulis says.