In new research from Ally Bank, nearly 20 percent of respondents said that hiding debt was a key issue that sparked ongoing money arguments. Here are five things that couples can do to steer clear of trouble:

Exchange numbers

No, not phone numbers. You need to share your credit reports and net-worth statements. Not just before marriage but before living together, as well. If there are worrisome signs such as late payments, maxed-out cards or towering debts, that is where you will find them.

Establish account access

You do not have to merge all your finances. Many couples are more comfortable with separate accounts. But you should at least trade logins and passwords so that financial information is available to partners if they want it. If your significant other becomes defensive at the idea, that is another warning sign.

Set ground rules

Set a level at which you have to discuss or clear it with your beloved, say, $100 or $500, when making a big purchase. This will help foster mutual trust and act as a natural barrier to outlandish or unnecessary purchases you may regret later.

Use budgeting apps

Think of apps like Mint, You Need a Budget, or EveryDollar as a kind of forced marital transparency. When you can see the account in one display, it makes it hard to hide a different set of off-the-book numbers. If that process brings secrets to light, then so be it.

Get it in writing

Arrange a cohabitation or prenuptial agreement. The process of writing down your expectations will reveal any serious money disconnects, and the earlier this happens, the better. That does not mean shaming or scratching off lower-income partners. After all, few spouses make exactly the same amount of money.