Which rewards cards are worth your time?

HOUSTON Now more than ever reward cards can really pay off. But you have to read the fine print because in some cases you could actually pay more in interest than you are getting back in rewards.

Bobby Johansen has flown many times for free, thanks to his Jet Blue Amex rewards card.

"If I make a lot of larger purchases, I generally do them on the Jet Blue card so that I can redeem as many flight points as possible," Johansen said.

Consumer Reports Money Adviser has sized up the best rewards cards.

But Chris Fichera says be aware, they're only worth it if you pay off their balance in full each month.

"These cards generally have higher interest rates," Fichera said. "So if you carry a balance, you could end up paying more in interest than you get back in rewards."

And watch out for hidden fees: 19 percent of rewards cardholders said they had increased fees for services like balance transfers, cash advances, and foreign transactions in the past year. And scrutinize the fine print.

"Some cards have clauses that can make you lose out on points or cash back," Fichera said.

Take the Discover card. It gives one percent cash back. But that drops down to 0.25 percent at warehouse or discount stores like Wal-Mart.

"The Chase Freedom card can be good because it offers 5 percent cash back in certain seasonal categories," Fichera said. "But since those categories change every quarter, you have to opt in every time, which can be a hassle."

Consumer Reports Money Adviser says one of the best cash back reward cards is the American Express Blue Cash. It doesn't charge an annual fee, and after spending $6,500 within a year, it offers 5 percent cash back at supermarkets, drugstores, and gas stations, and 1.25 percent elsewhere.

While some love the idea of rewards cards, other consumers say no thanks!

"I have done it before and I ended up spending more money than I got back for anything, so it really wasn't worth it," consumer Hannah Nelson said.

"Sometimes it's more complicated than it's worth, too many options to choose from, and you think the rewards are going to be so much more than they actually are, so for me I like straight forward offers as opposed to too much of a hassle," shopper Susan Steel said.

Retailers are offering rewards cards, too, and if you're a loyal customer, they can pay off. Consumer Reports says a good one is the Amazon.com Rewards Visa card. It has no annual fee, pays $30 back on your first purchase, and points are unlimited and never expire.

Because terms and conditions of rewards cards change frequently, be sure to routinely check for updated terms.