Not only do you have to worry about your significant other sneaking around behind your back with that hooker from the coffee shop, but a new survey says financial infidelity is a big problem for many Americans.

An online poll commissioned by ForbesWoman and the National Endowment for Financial Education (NEFE) and conducted by Harris Interactive, surveyed 2,019 U.S. adults from December 17 to 21 and found that 31% of those who combined finances had admitted to lying to spouses about money. Another third of those admitted they themselves had been deceived about money.

The leading crimes among the wronged and the perpetrators were hiding cash, minor purchases and bills. Others said they’d hid major purchases, kept secret bank accounts and lied about debt or income.

“A third of the population admits to not being honest with their spouse,” says NEFE chief executive Ted Beck. “That is a big number. These indiscretions cause significant damage to the relationship.”

For those couples experiencing financial infidelity, 67% said the deception led to an argument and 42% said it caused less trust in the relationship. A further 16% indicated the problem had led to divorce, and 11% reported a separation.

Time to fess up about that box of cash you hid behind the Sex and the City DVD collection where you thought he’d never look.

Is Your Partner Cheating On You Financially? [Forbes]

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