Much like emotions, time, and energy, money is very much on the list of things you’ll naturally invest in a relationship, whether you’re spending directly on your partner or on the things you do together. And just as the emotional and energetic investments you make for a partner have an effect on their livelihood, so, too, do the financial investments you’re capable of contributing to the partnership. As a result, withholding key financial details from a partner can be a form of infidelity, similar to physical or emotional cheating for the ways in which it misleads a partner about your overall commitment to the relationship.

“Whether or not you’ve chosen to merge your finances with a partner, your financial situation will likely affect your relationship,” says Maya Maria Brown, relationship expert and creative strategist at relationship wellness app Coupleness. “For example, if your partner wants to go on lavish vacations and expects to split the bill, but that’s not in your budget, you’d need to talk about your monetary approach to vacation planning. Or, if you’re expecting to receive an inheritance and plan to donate a large portion of it, but your partner would like you to keep it for your future together, there’s a discussion to be had there.”

“If you’re not honest about your financial situation upfront, it’s likely that when the truth eventually comes out, your partner will feel misled.” —Maya Maria Brown, relationship expert

Overall, the life-blending that happens in a romantic relationship tends to implicate the money of all parties involved—which is the big reason why keeping money matters a secret can have the effect of cheating on a partner. “If you’re not honest about your financial situation upfront, it’s likely that when the truth eventually comes out, your partner will feel misled,” says Brown. Not to mention, purposefully withholding any information from your partner about something that involves them can degrade trust in your relationship.

But just like with emotional and physical cheating, financial infidelity isn’t always so clear-cut in practice. Do you have to reveal everything about your financial picture to a partner? And at what point in a relationship should you share money matters? Below, financial and relationship experts break down what financial infidelity really looks like, why some people do it, and how steering clear of it by way of honest money talks can help safeguard your relationship.

What constitutes financial infidelity?

Hiding any financial matters from your partner in a way that deceives them about your financial status can be seen as a form of infidelity, says financial coach Dasha Kennedy, wellness expert at wedding-planning website The Knot. Even if you don’t intend on deceiving your partner, keeping secrets about the money you have (or don’t) can have that effect—much like flirting with someone who isn’t your partner could be perceived as emotional cheating even if you didn’t set out to cheat on or hurt your partner.

Because every relationship is different, however, there’s not a singular rule for which money matters should be divulged in order to avoid being financially unfaithful. That’s why it’s so important to align with your partner early about the money topics you will and won’t share in the same way you would communicate any other relationship expectations, says Brown.

Generally, however, if you would feel dishonest for not being open about a particular piece of your financial puzzle, that’s a good sign that withholding it constitutes financial infidelity, says Brown. “This could include any debt you have, like credit-card debt or student loans, savings, an impending inheritance, your credit score, any investments you’ve made, and your spending habits.”

Withholding these kinds of things can quickly rise to the level of financial infidelity because of the ways in which they’re linked with elements of your personality, your past, and the life you may be able to lead in the future. And in many cases, the consequences—good or bad—of these secret savings, debts, or investments will directly implicate a partner down the line, raising the question of why you hid them in the first place.

“One of the most common financial matters that I’ve seen spouses hide from each other is a personal credit card,” says divorce attorney Hailee Zabrin, income partner at the law firm Berger Schatz. “Often, one person will do this to charge personal expenses that they do not want their spouse to know about for whatever reason.” But then, should they not be able to pay the credit card charges with personal funds, the debt is suddenly the problem of the previously unknowing spouse, she says.

Even in situations outside marriage or where the partner is not made responsible for a financial matter that was previously kept from them, the act of withholding key financial realities can be considered infidelity. This is true for the same reason that making secret emotional investments could be considered emotional cheating: A partner doesn’t have to find out about an unfaithful act for it to constitute cheating.

Why are some people tempted to withhold the truth about their finances from a partner?

The underlying reason for financial infidelity is different in folks who are dishonest about a financial challenge (like debt, loans, or a credit-card spending habit) versus people who are hiding a financial perk (like a secret savings account, trust fund, or inheritance).

In the case of the former, it’s likely that the choice to keep it on the down low is springing from a place of shame or fear, says Brown. Perhaps they’re worried that their partner might think differently of them (or even leave them) should they find out about the secret debt or loans. Whereas in the case of the latter, the person may be holding onto a secret stash of money and may be struggling with trust issues or feeling unsafe in the relationship, says Brown.

“It’s best to be honest about money challenges, both because they could affect your partner, and so that your partner can help you work through them.”  —Brown

If you fit into the first category, Brown suggests speaking to a therapist in order to get more comfortable sharing what’s going on with your partner. “It’s best to be honest about money challenges, both because they could affect your partner, and so that your partner can help you work through them,” she says. And if you’re in the second category, it’s worth doing a bigger evaluation of the quality of your relationship as a whole. Holding onto money out of a lack of trust for your partner could signify that it’s time to leave the relationship, says Brown.

Why sharing financial matters with a partner is so important

As noted above, your financial standing directly implicates your partner’s livelihood. “A financial windfall like an inheritance, or challenges like debt, a bad credit score, or poor spending habits could influence your partner’s life,” says Brown.

For married folks, that influence is legal: “In the State of Illinois, for example, when two people are married and one spouse incurs debt during the marriage and then does not pay their creditors, those creditors can obtain a judgment against an asset that the spouses hold jointly,” says Zabrin. “If the judgment isn’t satisfied, the jointly held property can be sold or liquidated to satisfy the debt of just one spouse.”

But even in unmarried relationships, the financial status of one person could certainly have a direct effect on how the other can live their life. “Money impacts every decision you and your partner will make,” says Kennedy, “determining where you live, what type of dates you can go on, and even the decisions to have children or get married.” Though these things might not be on your radar early in a relationship, “once you start having conversations with a partner about merging aspects of your lives, talking about your financial situation is an important step in making those plans,” says Brown.

Perhaps the most essential thing to discuss with a partner first is your spending habits, says Kennedy. “Knowing your partner’s spending risk factors, or whether they tend to spend impulsively or responsibly, can help you get on the same page about investing, paying off debt, and managing bank accounts.” Once you’ve started having these kinds of money conversations, you can then dive even further into “how you’re feeling about your finances, what makes you nervous, and what’s on your wishlist,” says Brown.

Achieving this kind of deep financial alignment with a partner can be a major boon for the longevity of your relationship, helping you avoid the money disagreements often cited as a key cause of divorce.

And from an even bigger-picture lens, being open about money can engender more intimacy and connection in your relationship overall. Not only does talking about your finances free you from the stressful burden of keeping a secret from your partner, but also, it reassures your partner that you’re comfortable being vulnerable with them. (Whereas a partner who is lied to about money is bound to question what else you might be lying to them about, says Brown.)

In this way, financial compatibility and openness is important for reasons that stretch far beyond the practical, says Kennedy: “It plays such a huge role in the success of a relationship because it shows a couple’s ability to communicate effectively about sensitive topics.”