In an ideal world, married people talk about their money. They discuss shared goals, income, expenses, and their spending habits. When disagreements arise, they can reach a compromise or find a solution.

But, that’s not always the case. People aren’t perfect and neither are their finances.

Experts may consider it financial infidelity when you fail to share financial information, including how much you earn and how much you spend, with a life partner. But if you withhold information about your earnings and expenses from not just your spouse but the Internal Revenue Service, you could be courting even bigger problems.

When you’re filing a joint tax return, both partners on the form are held responsible for paying any taxes owed. The IRS calls this “joint and several liability.”

However, in specific circumstances, a person can file for Innocent Spouse Relief, leaving the tax liability to their partner.