53% of Americans have kept money secrets from their partner—yet only 27% say they've committed financial infidelity

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If you're unclear about what constitutes committing "financial infidelity" against your partner or spouse, you aren't alone.

In 2018, researchers from the University of Southern Mississippi polled 414 U.S. residents on the topic. The survey's findings, which were published in the Journal of Financial Therapy, show that more than half (53%) of participants said they had kept money secrets, such as hiding receipts or lying about the price they paid for a particular item, from their partner. And yet, just 27% of respondents admitted to having committed financial infidelity.

However, experts say keeping money secrets from your significant other — no matter how big or small — technically counts as financial infidelity.

"Financial infidelity is hiding financial decisions intentionally (or unintentionally), from an invested partner," says Adam Holt, CEO and founder of Asset-Map, an online financial advising resource.

Peter Hoglund, a certified financial planner with New Jersey-based Wealth Enhancement Group, agrees. "Financial infidelity is making a material financial decision or purchase that you believe your partner would oppose, so you hide this decision from them," he says.

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In the U.S., financial infidelity is common. Nearly half (41%) of American adults who combine finances with a partner or spouse admit to committing financial deceptions against their significant other, according to a 2018 survey from the National Endowment for Financial Education.

Here are some of the most common ways Americans keep money secrets from their partners, according to the University of Southern Mississippi survey:

  • 24% of respondents report hiding purchases or receipts
  • 23% of respondents report lying about the price of something
  • 22% of respondents report spending money on children behind a spouse's back
  • 19% of respondents report saying a purchase was on sale after paying full price
  • 11% of respondents report secretly withdrawing money from savings
  • 11% of respondents report secretly getting a new credit card
  • 7% of respondents report covering up debt
  • 4% of respondents report hiding a raise or bonus

However, financial infidelity and the varying extremes that often go along with it can be thought of as a spectrum, says Judith Newman, a best-selling author and journalist.

"Some stealth might not qualify as financial infidelity — say, the daily Frappuccino you don't tell your spouse about," Newman writes in a recent article for AARP the Magazine. But "at the other end of the spectrum are major offenses — actions that, when they blow up, threaten a couple's financial security. That could mean borrowing or spending thousands of dollars, or cheating on taxes without a spouse's knowledge."

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It's important to know that "infidelity," as it's often thought of in relationships, isn't just a word that's reserved for the bedroom. "Infidelity can hit the pocketbook and wallet, too, when one spouse spends, borrows, withholds or hides money without telling his or her partner," Newman writes. "Such financial infidelity can damage a marriage just as much as the sexual type, if not more so."

Instead of turning to financial deceit when faced with money struggles, it's important that you and your partner try to work toward practicing open and honest communication, says Kristin O'Keeffe Merrick, a financial advisor of O'Keeffe Financial Partners.

"Money communication is incredibly important in a long-term relationship," says O'Keefe Merrick. "I have seen several cases of financial irresponsibility and infidelity that have ruined relationships. If you and your partner are having a hard time communicating about it, I suggest engaging a third party."

"It may make sense to see a financial therapist together," O'Keefe Merrick adds. "And, please, be very careful about marrying if you have serious concerns about the other's financial situation."

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