If you have a credit card balance that you have never revealed to your partner, a secret savings account slush fund or a weakness for $20 chocolatinis, you may be committing financial infidelity.

Hiding debts and impulse buys from loved ones can break a relationship, according to several recent surveys and studies. Oddly enough, financial infidelity can also spice things up.

In a new survey by Edelman Financial Engines, 39% of married adults admitted that their partners didn’t know everything about their spending. For divorcees, the figure rose to 50%. The survey reached 2,022 adults.

Another poll found that roughly two-thirds of partnered adults hid purchases from their partners in the last year. The average secret spender concealed $475 in loot. That survey, by Circuit for Teams, reached 1,049 respondents.

A third report, from NerdWallet, found that one-third of Americans with credit card debt told no one what they owe. That survey covered more than 2,000 people.

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Does 'financial infidelity' count as actual cheating?

The prevalence of financial infidelity poses a paradox. More than half of us think financial infidelity amounts to cheating, according to another survey, from The Motley Fool Ascent.

Yet, in the very same poll, roughly half of married adults admitted hiding purchases from their partners. The 2022 survey covered about 1,500 adults.

“It’s not just about hiding debt,” said Matt Frankel, a certified financial planner who writes for The Ascent. “It can also be lying about how much you’ve paid for a large purchase. If I buy a large TV and tell my wife it was on sale, and it wasn’t, that’s financial infidelity.”

Men are more likely to hide purchases than women, The Ascent found, by a margin of 56% to 43%.

“In my experience, women are more likely to hide prices,” Frankel said, meaning they may tell a partner they spent less money than they actually did.

Men hide spending on electronics, alcohol and gambling. Women hide clothing and cosmetics

Do men and women hide different kinds of purchases? Oh yeah. There’s not much overlap, Frankel said.

Men conceal pricey electronics buys and spending on alcohol and gambling. Women are most likely to hide purchases of clothing, cosmetics and gifts for people other than their partner, he said.

Surveys consistently find that younger people are more apt to keep financial secrets than older Americans.

Bankrate found that rates of financial infidelity decline by generation: 63% of Gen Zers and 54% of millennials reported keeping financial secrets, compared to 29% of Gen Xers and boomers. That survey queried 2,542 adults.

“Where you are at the age of 24 is very different from where you are at 68,” said Sara Rathner, personal finance expert at NerdWallet, whose research found a similar generational pattern. “Your relationships are newer, and you may not have been intertwined with another person for very long.”

When a money problem becomes a relationship problem

With financial infidelity, a money problem can become a relationship problem.

"Sometimes the financial management piece is easier to solve than the relationship piece," said Bruce McClary, spokesperson for the National Foundation for Credit Counseling. "And sometimes it's the other way around."

In the Edelman survey, Americans rated dishonesty and obfuscation as their top financial “deal breakers” in a relationship.

Bankrate’s research, by contrast, found that “people are remarkably forgiving” about a partner’s secret purchases or hidden debts, said Ted Rossman, a senior industry analyst at the personal finance site. “The vast majority said they wouldn’t leave a relationship over debt.”

A lot seems to ride on the magnitude of a financial transgression.

McClary, the foundation spokesperson, used to work as a credit counselor. He recalled a particularly dire case of financial infidelity.

“A couple came to my office for what I thought was just going to be an hourlong budget review session,” he said. “I noticed something was a little off because they weren’t speaking to each other.”

McClary also noticed that one spouse carried a large grocery bag in his lap.

The bag was stuffed with credit card bills, many of them unopened. Just before the couple headed to the counseling session, the husband had revealed to his wife that he had “somewhere around 20 credit card accounts that she was not aware of,” McClary said.

“The reason why was heartbreaking. He had lost his job and didn’t want his wife to know, so he started applying for lines of credit to keep things afloat. You can only play that game until you run out of lines of credit. And that’s what happened.”

That couple, McClary said, seemed to be headed for divorce court. But not all financial indiscretions end so badly.

Can financial infidelity actually be good for a relationship?

One provocative paper, published in the April issue of the Journal of Consumer Psychology, reported that hiding purchases from a partner can actually be good for a relationship.

Researchers found that financial infidelities sparked guilt. Guilt, in turn, prompted greater “relationship investment” by the guilty party toward the partner, the researchers found.

“You end up wanting to do something to alleviate that guilt,” said Kelley Wight, an assistant professor of marketing at Indiana University and co-author of the paper. “Maybe you’ll want to spend more money on your partner on Valentine’s Day.”

To be sure, many of the financial transgressions tracked by Wight and her colleagues sound mundane, even poignant: A spouse who made a clandestine $80 Sephora purchase. A partner who secretly hired a cleaning service before their partner returned from a trip. A spouse who snuck out to McDonald’s while their partner was trying to lose weight.

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When is a purchase big enough that you should tell your partner?

When is a purchase or debt large enough to qualify as something you really ought to disclose to your partner?

Frankel, of The Ascent, reasons that anything over $250 is worth flagging to your loved one.

Rathner, of NerdWallet, sees the infidelity threshold as more of a sliding scale.

“For a couple with a shared income of half a million a year, that number might be a thousand dollars,” she said. “For a couple that’s making $80,000 combined, they might want to talk if an item costs more than $150.”

Wight, the IU researcher, says most of us know when we are about to commit a financial indiscretion.

“People tend to have a pretty good moral compass,” she said. “If you’re starting to feel really guilty, that’s a sign that something is wrong.”