Trust is the foundation of any relationship. That trust includes financial issues as well as personal ones. Do you trust your spouse or partner enough to be open about your finances? According to a recent survey from, 5 percent of respondents admitted to keeping a checking account, savings account, or a credit card secret from their partner.

Sometimes the reason is unpleasant to face — a person wants to be able to do and/or buy things that they want to hide from their partner for selfish reasons, or even to hide illegal or immoral activity. In other cases, a person may have good motives that went awry. He or she may be salting money away in a separate account for a surprise second honeymoon, or extending credit into a family business where the spouse is uninformed or uninterested.

Surprisingly, secret accounts were more prevalent among older Americans. Respondents aged 63 to 71 were almost four times more likely than millennials to have a concealed account (11 percent to 3 percent). In addition, older respondents were almost twice as likely to spend $500 without notifying their partner as compared to millennials (39 percent to 20 percent).

Over a quarter of all survey respondents (28 percent) had spent $500 or more without notifying their partner, while one-third of respondents were okay with their partner spending $500 or more without letting them know about it. That's fine if those respondents were matched with each other, but there are certainly many cases where partners have differing approaches to spending.

It's important to have some degree of spending independence in a relationship, but it's also important to come to an agreement about spending boundaries. As with many aspects of successful relationships, good communication is the key. The ability to compromise also helps.

What do you do if you find that your spouse or partner has kept an account secret from you? Openly discuss why the account was secret, assess the situation, and figure out how to move forward.

Even if your partner has racked up considerable debt, you can get through it with the right approach and proper motivation. When overspending has produced excessive debt, Adam Carroll, Founder and Chief Education Officer at National Financial Educators, uses the sports analogy of "great offense and great defense" to address both income and expenses. "Great offense is 'How do I make more money?' ... defense is 'How do I decrease my monthly expenses to the absolute ridiculous?'"

You must also review the effect of this secret account on your collective credit. While each of your credit histories and credit scores are independent, any joint credit such as a future mortgage loan could be affected.

"Everybody in the U.S. has their own credit history," says Rod Griffin, Director of Public Education at Experian, "but if you apply for joint credit, both [histories] are going to be considered. So it's hugely important to take care of your credit history, especially if it's struggling a bit." If the hidden account would increase the collective credit risk, it may be necessary to focus on building that score up before opening joint accounts of any sort. To learn more about credit, download our free eBook, Give Yourself Credit.

The effects of the joint account will be reflected on your individual account, so make sure that you and your spouse have a sufficient level of trust before embarking on any joint account.

Secret accounts are nothing new, nor are they rare. Should you find that your spouse or partner has been hiding an account from you, just remember that you are not alone — and if you are entering into a more serious relationship, consider having the talk on financial openness sooner rather than later.

If you want to reduce your interest payments and lower your debt, try the free Debt Optimizer by MoneyTips.

This article was provided by our partners at MoneyTips.