Cheryl Cade’s boyfriend, an actor in Los Angeles, gave her a $100 gift certificate at MAC Cosmetics, which she planned to use to buy a dark red lipstick.

That was in 1999.

“I was saving it at first because it was so special,” the Dallas-based marketing director for a tech company, said.

Since she received the gift certificate, which is a physical piece of paper, Cade has moved four or five times, from L.A. to San Francisco to Texas. It’s gone with her, and 21 years later, she still plans to use it for the perfect shade of red.

“I’m frightened the person I try to use it on will be younger than the gift certificate itself and won't know what to do with it,” Cade said. She’s had several relationships since then, but she still keeps in touch with her ex. “It’s almost a souvenir of the relationship and he’s a great guy.”

It’s now a full month past the holidays, and many Americans are sitting on what economists estimate is billions of dollars stashed onto gift cards.

Wait too long, and the stores could go bankrupt or cease to exist. On Tuesday, Macy’s announced that the department store plans to close 125 — or one-fifth — of its locations over the next three years.

For most people, the reasons for delaying the use of gift cards are emotional, explains Suzanne Shu, associate professor of marketing and behavioral decision-making at the University of California at Los Angeles’s school of management, who has researched the procrastination of positive experiences.

“People delay using gift cards because they want to use them at the ‘right’ time,” Shu said. “For example, if someone received a gift card from Starbucks, they might think that they’ll save it for a special splurge rather than using it on their everyday coffee.”

Sound familiar?

“This gets even more extreme if the gift card is really special and not something a person would buy for themselves,” such as a gift card for a fancy restaurant, Shu added. “Then the recipient feels like it has to be saved for an equally special occasion, such as a birthday.”

She calls this tendency “occasion matching.”

Shu said that while this is “totally rational decision-making,” the card might get forgotten, lost or expire while waiting for that quintessential special occasion.

Jamie Ferrel, 34, an education consultant at a nonprofit in New York City, is sitting on a pile of gift cards to Trader Joe’s, Fandango and the upscale Brooklyn restaurant, Olmstead, the result of getting married last summer along with the usual holiday haul.

“I’m pretty good at going through them,” Ferrel said. “I try to spend the whole thing at once, if possible, to not to waste random balance.”

But as a giver of gifts, she knows that many cards go unused, and it affects her own behavior. “I tend to not give them to people because I know it’s likely they may not use them. I don’t know if the money [on gift cards] is the best spent.”

Those smaller incremental balances, can add up unless you start keeping track. Robin Fusco, a writer in Los Angeles, has come up with a workaround for those.

“I used to lose money when prepaid Visa cards, the kind you get for rebates and refunds and the like, would expire,” Fusco wrote in an email.

“Something like $50 is easy to use, but when I'd end up with smaller amounts like $6.27, I'd run into issues with stores not being able to split payment, etc. Now, I use those small amounts to reload my Amazon gift card balance. I don't lose a cent, and the Amazon balance never expires,” Fusco said.

Psychologically, prolonged expiration dates don’t ensure cards get used. Rather, it’s often the opposite. In some states, like California, expiration dates are illegal.

“Longer expiration dates can also make the likelihood of successfully using the card go down,” Shu said.

For example, most people would save something like a free pass to Disneyland for a special occasion. But in reality, weekend after weekend, the pass goes unused as causes for celebration come and go.

“You decide to save it for an even better special occasion, and the delay cycle starts all over. After a while, the threshold for how special the occasion has to be to finally use the gift card is outrageously high and it’s psychologically very difficult to actually use it.”

Her expert advice? Use cards by a specific date, calendaring it if you have to. “Enjoy the experience of consuming it.”

For Cade, though, even the nudge from an expert may not cut it.

Would this interview finally prompt her to go to a MAC counter for that perfect shade of red?

“I have a weird feeling that I won’t.”

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