For the sixth year in a row, gift cards were the No. 1 requested item this holiday season. Yet even they can go wrong.

Maybe you’re a movie person, and Aunt Annie gave you a gift card to REI. Or perhaps you scored a Starbucks gift card at the office Yankee Swap, but you don’t drink coffee. There are numerous reasons why a store or restaurant gift card could end up tucked away in a drawer.

If you’re stuck with one of these cards, remember that it’s not worthless. The trick is to unlock the cash.

Several gift card exchange websites have popped up that connect people who don’t want their gift cards with people who do. Some, such as Gift Card Granny, simply link to sites that are selling discounted gift cards such as eBay, Amazon and smaller sites that specialize in gift cards. Other sites, such as Plastic Jungle, buy the gift cards and sell them directly.

I recently spoke with the CEO of Plastic Jungle, Margaret Mackenzie, about the site, how it works, and what consumers should know.

How would you describe your site?

First thing, we offer our buyers a guarantee. It’s not just an exchange. We act as a principal in the middle. We want to be able to say that if you buy the card, we guarantee the value of the card.

Which gift cards do you accept?

We don’t handle gift cards that come from the big open-loop players (translation: those general-purpose gift cards with Visa, American Express, Discover or MasterCard logos on them). We handle retailer gift cards that are closed-loop (translation: only used at a specific store or brand) and with no expiration dates. (Federal law requires gift cards to be good for at least five years, but 95 percent of gift cards recently surveyed by Bankrate had no expiration date.) Generally, we don’t take gift cards with less than $25 on them. In some cases, we will take a $10 minimum.

How do you determine at what price to buy and sell gift cards?

The demand for the brand, the time of the year, and the amount of money left on the card determine the price and discount.

If it’s a gift card issued by a national retailer that everybody shops at, then we will offer a better price (to the gift card seller, although it will be less than the value on the card.) If it’s a card for an equally great retailer with a smaller market share, the price won’t be as great. During the holidays or back-to-school time, the velocity of sales on the site increases. And generally a $5 gift card doesn’t move as fast a $100 card.

Do buyers of the gift cards get the actual gift card?

We have a mix of physical and digital gift cards on our site. If a retailer will accept a card digitally, either online or in the store, then we will process the sale digitally. If the retailer won’t process it digitally, then we will handle it physically (and send the actual gift card to the buyer).

So even though you won’t get the full value of what’s on the gift card, you’ll get some money from it. And that’s better than not using it at all. For buyers, a discounted gift card means you can get more for your money when you shop.

Have you bought or sold discounted gift cards? What was your experience like?

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