Science says: this is how much sex couples who call themselves the happiest really have

Once a week, three times a week, or sometimes not at all for weeks? If you've been with someone long enough, there comes a moment when you wonder: are we actually doing it often enough? Especially when your friends enthusiastically talk about their wild sex lives and you mainly think about that one time last month when you both didn't fall asleep halfway through.

Fortunately, science has also looked into this. And the answer is surprisingly simple: for couples who feel happy and satisfied with their relationship, having sex about once a week comes up quite often.

But before you go ahead and schedule a fixed sex night in your calendar: it's not that black and white, of course.

It's not just about how often you have sex

That people with a partner have sex more often than singles will not really surprise anyone. Dutch figures from the CBS show, for example, that in 2022, 83.3 percent of people who were part of a (married) couple had had sex in the twelve months prior. Among singles and people in a single-parent household, that was 48.6 percent.

Among 16 to 35-year-olds living with a partner, that was even at 98.2 percent, compared to 73.7 percent among peers who did not live with a partner.

But that doesn't answer our real question yet. Because having sex is one thing, but how often? And does that then say something about how happy you are with your relationship?

Once a week turns out to be an interesting number

For that, we need to look at a well-known study from 2016. In this study, a total of 30,645 participants were examined across three studies, looking at the relationship between sexual frequency, relationship satisfaction, and well-being.

What turned out? People who had sex more often generally reported more well-being and relationship satisfaction. But there was a sort of maximum: from about once a week, having sex more often was no longer associated with extra well-being. In other words: having sex three times a week doesn't automatically mean it's three times as enjoyable.

And no, that doesn't mean that science has determined that you must be in bed every seven days. The research shows a correlation, not a manual for a happy relationship. If you both enjoy having sex three times a week, just keep it up.

But how much sex do happy couples have then?

A more recent study from 2025 makes the answer even more interesting. Researchers looked at 2,101 couples from the German Family Panel and examined different combinations of sexual frequency and relationship satisfaction. The largest group, accounting for 86.38 percent of the couples, consisted of couples who scored high on relationship satisfaction and had sex relatively often. It turns out their average was just under once a week.

Look, there we have a number. But the interesting thing about this study is that sex was certainly not the only factor at play. Low conflict, openness to each other, and commitment were also associated with a greater chance of that combination of high relationship satisfaction and an active sex life.

And honestly: that might sound less exciting than a secret sexual frequency, but it actually makes a lot of sense. A relationship where you can communicate well, feel safe, and still find each other attractive is likely also a relationship where sex finds its place more easily.

So are couples who have sex more often happier?

Not necessarily. That's exactly where we need to be careful with such research. The fact that sex and relationship happiness are correlated does not automatically mean that more sex makes you happier. It can also work the other way around. If your relationship is going well, you might simply feel more inclined to seek each other out between the sheets.

And besides: what is a lot for one couple is hardly enough for another. One person loves having sex three times a week, while the other is already overjoyed if there is time for a kiss without someone unloading the dishwasher after a busy work week.

And what if you have sex much less often?

Then there is still no reason to panic. There is no scientific or biological meter that suddenly gives your relationship a failing grade after seven days without sex. As long as you are both satisfied with your sex life, there is not automatically something wrong.

It becomes especially difficult when your needs are very different. If one person wants sex every night and the other hardly ever does, that can certainly lead to frustration. Not because a certain number of times a week is ‘healthy’, but because the difference in needs between partners can create tension. The most important number might therefore not be a number at all: are you both happy with it?

Image: Netflix | Eating Club