Editors' pick: Originally published Dec. 12.

American adults are prone to overspending during the holidays, and many actually hide purchases and spending from their partners and spouses.

That insight comes from Joseph Grenny and David Maxfield, cofounders of VitalSmarts and the authors of the business bestseller Crucial Conversations. Their research found that eight out of ten U.S. adults "either overspend or have a spouse or partner who overspends during the holiday season, and nearly 56% say it is difficult to discuss holiday spending with their spouse/partner."

According to VitalSmarts research, here's how bad the problem is for U.S. households, with percentages of consumers who perform the following actions when it comes to holiday spending:

  • Change or avoid the subject - 60%
  • Hide price tags or what's been spent - 55%
  • Hide recent purchases - 43%
  • Use separate accounts to make the purchase - 33%
  • Walk away from the conversation - 26%
  • Tell spouse/partner it's their money - 19%

Relationship experts say that money is a common source of angst between couples and that financial issues really heat up during the holidays.

"Like most issues though, this can be fixed with direct, thoughtful communication," says Erika Kaplan, a Philadelphia, Pa.-based matchmaker with Three Day Rule. "Couples need to sit down together and devise a holiday fund budget so there are no secrets and no surprises."

So what are the "red flags" that indicate a partner or spouse is hiding holiday spending?

"There are several," says April Masini, a New York City-based relationship and etiquette expert and author. "Start with ATM cash withdrawals. You'll see records of cash withdrawals on your bank account statements, but no receipts for cash purchases."

Masini says that when a partner wants to hide purchases, he or she will try not to leave a paper trail; using cash is a way to do that. "If they're new to hiding spending, they'll probably not worry too much that there are ATM withdrawal transactions showing, and they'll just brush those off when asked about them," she says.

Also watch out for purchases with price tags removed, Masini, adds. "You may find random new purchases around the home, with no price tags, or you may stumble on a stash of new purchases, all of which are missing price tags," she says. "If a partner wants to hide spending amounts, without hiding spending, they'll let you know they've shopped - just not to what degree they've spent. If you ask about the prices, they'll brush it off and claim that they don't know and it's not important enough to keep track of."

Another sign of toxic holiday spending in the house - price tags in the garbage. "On the flip side, you may find price tags in the trash with no knowledge of what they belong to," Masini says. "This is your clue that the items connected to those price tags are being hidden, and the tags weren't meant for your eyes."

When you do have that conversation that Kaplan recommends that couples address the problem calmly and without finger pointing. "Ask questions naturally, and not in an accusatory tone," Masini says. "For example, 'I found a credit card statement in the mail that I don't recognize. Do you know what it is?' That's better than, 'You took out a line of credit without telling me!' The former script opens a conversation and asks for input. The latter is accusatory and invites an angry partner to walk out, not engage in conversation."

Also, create a regular money meeting where you discuss your financial behaviors and transactions, Masini adds. "There's a key benefit created by a secret spending issue - you can forge healthy communication and make a money plan for your relationship," she says. "Many people avoid money issues because they carry hurt feelings. Get past that. Have your discomfort, but don't let it stop you from having an open and healthy relationship with money within your romantic relationship."

When you're engaged in a discussion, quietly or animated, try to dig down and get at the root of the problem.

"When spouses hide expenses and overspend, it's usually due to some need not being met," says Adam Torres, a financial planner at Century City Wealth Management, LLC, in Los Angeles, Ca. "While every relationship is different, I coach clients to first have an open dialogue about finances and the true state of where the family stands financially."

Once that dialogue is active, Torres advises building a "realistic budget" for the holidays. "The budget becomes real when it is written down and agreed on by both spouses," he states. "Make the budget specific or it will not work. For example, don't simply say that you are going to cap spending at $2,000 this holiday season. State specifically where the money will be spent."

If possible, creating a "slush fund" for the holidays is the best route, he adds. "This will keep both spouses on track and neither party will feel guilty for the splurge at the end of the year for the extra holiday spending," says Torres.

The moral of this Christmas story? Don't hide financial moves around the holidays. It will keep things merrier and leave more cash on hand for one of the things spouses and partners care about most - each other.