Most married couples in the United States have sex about once a week, though the number varies widely by age, relationship length, and individual circumstances. Roughly half of U.S. adults between 18 and 44 report having sex at least weekly, while others settle into a rhythm of a few times a month or less. There’s no single “normal” number, but the data paints a clear picture of what’s typical across different stages of life and marriage.
Average Frequency by Age
Age is the single strongest predictor of how often couples have sex. Kinsey Institute data shows a steady decline across decades: couples aged 18 to 29 average about 112 times per year (roughly twice a week), those in their 30s average 86 times per year, and couples in their 40s come in around 69 times per year. A 2025 study found that people in their 20s have roughly 80 sexual encounters per year, which drops to about 20 times per year by the 60s.
Among adults 25 to 44, about half of both men and women report having sex at least once a week. For the youngest adults (18 to 24), the picture is a bit more uneven: 52% of women but only 37% of men in that bracket reported weekly sex, likely reflecting differences in relationship status at that age.
How Marriage Length Changes Things
Frequency tends to decline the longer a couple has been together. This is one of the most consistent findings in relationship research. The drop isn’t necessarily a sign of trouble. Early in a relationship, novelty and heightened desire drive more frequent sex. Over time, couples often settle into a lower but stable rhythm that reflects their day-to-day energy, health, and competing demands. The steepest decline typically happens in the first few years, with frequency leveling off more gradually after that.
The Once-a-Week Happiness Threshold
One of the most cited findings in this area comes from a study that explored whether having more sex makes couples happier. Researchers asked some couples to double their usual frequency. The result was counterintuitive: couples who had more sex didn’t report greater happiness. In fact, they reported slightly lower enjoyment and desire, likely because sex felt more like an obligation than a spontaneous act.
Separate research found that 86% of couples who were highly satisfied in their relationship had sex just under once a week. The takeaway isn’t that once a week is a magic number. It’s that quality and mutual desire matter far more than hitting a specific count. Couples who pushed beyond their natural rhythm didn’t gain anything from it.
What About Sexless Marriages?
About 7% of married adults in the U.S. haven’t had sex in the past year, and 4% haven’t in the past five years. When you include couples having sex only a handful of times per year, that number rises to roughly 14 to 15%. That means about one in seven married adults lives in a relationship with little to no sexual activity.
A sexless marriage doesn’t automatically mean an unhappy one. Some couples arrive there because of health conditions, medications, or physical changes that make sex difficult. Others simply find that their desire has shifted, and both partners are content with the change. The problems tend to arise when there’s a mismatch: one partner wants more intimacy while the other doesn’t, and neither talks about it.
Why Frequency Declines Over Time
You might assume the usual suspects are to blame: kids, exhaustion, long work hours. But large-scale analysis of U.S. survey data found that none of these factors meaningfully explained the broader decline in married sex over recent decades. Controlling for the presence of children, employment status, work hours, education, and even religious participation made no real difference in the numbers. Pornography use didn’t explain it either. In fact, adults who watched porn reported slightly more frequent sex, not less.
The two factors that did stand out were age and spousal unemployment. Older adults predictably have less sex. And women whose spouses were unemployed were significantly less likely to have weekly sex, with a gap of about 11 percentage points compared to women whose spouses were employed. This suggests that financial stress or shifts in relationship dynamics around employment play a meaningful role, at least for some couples.
What Predicts a Satisfying Sex Life
Frequency and satisfaction tend to travel together, but the relationship isn’t as simple as “more sex equals happier marriage.” Research on couple profiles found that the happiest pairs shared several traits beyond just having regular sex. They had infrequent conflict, high levels of openness with each other, and strong mutual commitment. Couples who lacked these qualities but still had moderately frequent sex (two to three times per month) often had one partner who was dissatisfied, even if the other felt fine.
About 10% of couples in the research fell into profiles where partners disagreed on how happy they were, split fairly evenly between cases where the man was more dissatisfied and cases where the woman was. Only about 4% of couples landed in the low-satisfaction, low-frequency group. The vast majority of couples who communicated well, managed conflict, and stayed emotionally connected also maintained a sex life that worked for both of them. The frequency followed from the relationship quality, not the other way around.