There’s a general consensus that honesty is key to a healthy relationship.

Case in point: The 2015 Way We Are Now survey, which polled 6,000 people in the U.K., found that 70 percent of respondents value it over anything else—including communication, commitment, and even sexual attraction—when it comes to romantic success.

But are there ever times when fibbing might actually be better for your relationship?

“As a therapist, I don’t generally suggest lying to your partner,” says relationship expert Julie de Azevedo Hanks, Ph.D., licensed clinical social worker, director of Wasatch Family Therapy.

“However, I do think there are situations where it is appropriate to lie or leave out details,” she says. 

Here are six of the most common things couples tend to lie about in relationships, according to Hanks.

Plus, her take on how important it is to be totally honest in each scenario:

1. Your Finances

“Whether it’s ‘okay to lie’ really depends on the specifics of the situation,” says Hanks.

Lying—or withholding the details—about the fact that you went over budget on a new watch is different than not telling her that you have racked up $50,000 in credit card debt over the past year, she says.

Ask yourself this: How much of an impact is this going to have on my relationship and on my partner’s life? If the answer to that question is “a whole lot,” says Hanks, it’s important to tell the truth.

If you both work and keep your accounts separate, and you each pay for half of the bills, then buying those high-end headphones are more of a personal purchase. “But if you share an account and your agreement is that you will pool your money and you get a significant raise, but don’t disclose that so you can keep putting your old salary amount into your collective funds, that’s really not okay to lie about,” she says.

2. Where You’ve Been

“If you get up and tell your partner that you’re going to work every day when in fact, you’ve been laid off for two months, that lie has the potential to severely damage trust,” says Hanks.

But if she asks why you’re late getting home, and you share that you stopped to visit a sick buddy, but leave out the fact that you stayed a little longer than necessary, that’s okay. “It’s not a trust-breaker,” says Hanks.

If the line seems fuzzy, ask yourself whether she would feel betrayed or deceived by the details you left out. If the answer is yes, you should probably tell the truth.

3. Your Past Relationships

If your partner asks you questions about your past relationship—like where and how you had sex with them, how good she was in bed, or how she compares to your ex in bed—it’s okay to leave out the details and share more generalities, says Hanks.

Ask yourself these questions before you respond: How relevant is this information to my current situation? Will this cause more closeness or distance in my current relationship?

4. Your Attraction to Someone Else

When it comes to being honest with your partner about your attraction to other people, it’s important to ask: What will be gained or lost by sharing this information? 

If you think a co-worker is kind of attractive, she says, you probably don’t have to disclose that.“But if you are having intense feelings for a co-worker and it’s impacting your connection with your partner,” she says, “that’s probably a discussion to bring into the relationship—assuming you want to stay in your current relationship.”

5. Parenting Slip-Ups

In general, fibbing when it comes to parenting is a bad idea, but once again, the size and scope of the lie determine just how much of a bad idea it is.

“I don’t think it’s ever a good idea to go against the other parent’s boundaries,” says Hanks. “That said, it’s not the end of the world if you give a kid a cookie on the sly even though she hasn’t finished her veggies, like the other parent requested. If something is an isolated incident, it’s likely not a big deal.” 

When it comes to ongoing patterns of sabotaging the other parent’s boundaries, though? It’s not okay. 

The bottom line: Secrets impact relationships—period, says Hanks. “Even if your partner doesn’t consciously know you’ve lied, you know it, and it will have some sort of effect,” she says. “You may find it more difficult to be vulnerable with your partner, or you may start withholding other information.”