Natsal: what Britain’s national survey of sexual attitudes found

The National Surveys of Sexual Attitudes and Lifestyles, known as Natsal, are among the largest and most detailed scientific studies of sexual behaviour in the world. A new survey has been carried out about every 10 years since 1990, and more than 65,000 people have taken part.

People are chosen at random from across Britain, so the results broadly reflect the population. Trained interviewers visit them at home, and people answer the most sensitive questions privately on a computer.

Natsal’s findings have helped shape UK sexual health policy, including the National Chlamydia Screening Programme and the HPV vaccination programme.

In Natsal-3, men aged 16 to 44 reported an average of 11.7 opposite-sex partners in their lifetime, and women 7.7. A small number of people with many partners push these averages up, so the typical (median) number was lower: 6 for men and 4 for women.

Women reported more partners than in earlier surveys, and Natsal says the gap between men and women is narrowing.

Same-sex experience was also more common among women. 16% of women and 7% of men aged 16 to 44 said they’d had some sexual experience or contact with a partner of the same sex. Fewer, 8% of women and 5% of men, had had genital contact.

Half of men had had 6 partners or fewer, and half of women 4 or fewer.

People aged 16 to 44 who’d had an opposite-sex partner in the past year had sex a median of 3 times in the past 4 weeks, a little less than once a week. Natsal says how often people have sex has fallen over the past two decades.

People keep having sex at all ages, but how often, and the range of things they do, falls with age. Most people with a partner had vaginal sex in the past year, oral sex was common up to middle age, and almost 1 in 5 people aged 16 to 24 had anal sex with an opposite-sex partner.

People keep having sex at every age. Read more in “Anal sex research: what it tells us about consent, pain and STIs”

Natsal-3 also tested urine samples from 4,550 people aged 16 to 44 for STIs. It found that:

• HPV was the most common STI, followed by Chlamydia
• around 1 in 100 people had Chlamydia, rising to almost 1 in 20 women aged 18 to 19 and 1 in 30 men aged 20 to 24
• HIV and Gonorrhoea were each found in around 1 in 1,000 people

More people had had an HIV test or been to a sexual health clinic in the past 5 years than in 1999 to 2001, and the rises were biggest among people with more partners.

Many STIs cause no symptoms, so testing is the only way to know. Read more in “STI symptoms: what to look out for and when to test”

Natsal-3 also asked whether anyone had ever made people have sex against their will. 1 in 10 women and 1 in 71 men said this had happened to them since the age of 13. In most cases, the person responsible was someone they knew.

Consent can be withdrawn at any time. If someone has made you have sex without your consent, support and medical care are available, whether or not you decide to report it to the police.

Natsal-4 interviewed about 19,000 people aged 16 to 59 between September 2022 and April 2024. Because of the COVID-19 pandemic, it used a mix of face-to-face, telephone and online interviews, and it included extra people aged 16 to 29.

For the first time, Natsal-4 asked about online sexual activity, such as porn and sexting, and included transgender and non-binary identities. It also tested samples for Chlamydia, Gonorrhoea, Mycoplasma genitalium, Trichomonas and, in women, HPV.

The first Natsal-4 results are due at the end of November 2026. They’ll be the first full Natsal survey results for more than a decade.

UK guidelines recommend an STI test every year if you’re sexually active, after a new partner and at the start of a relationship. If you’ve had several partners since your last test, testing every 3 months is a good idea. After sex without a condom, if there’s a chance of HIV, get urgent medical care about PEP, emergency medicine that has to be started within 72 hours. You can also test:

• for Chlamydia and Gonorrhoea from 2 weeks after sex
• for HIV with a lab test, which is reliable from 45 days after sex
• for Syphilis, with a repeat test 3 months after sex

Whatever the averages say, a test is the only way to know you’re clear. Read more in “How many women have sex without a condom?”

Better2Know offers:

• Full Screen: tests for 7 infections, including HIV, Syphilis, Hepatitis B, Chlamydia and Gonorrhoea, from 28 days after sex, with results in 3 days (5 days for the home test).
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• Platinum Screen: tests for 12 infections, including HIV, Syphilis, Hepatitis B, Hepatitis C and Trichomonas, from 28 days after sex, with results in 3 days.

You can book any of these at one of our clinics. If you test before 45 days, a negative HIV result needs a repeat test. A Syphilis test in the first 3 months after sex can miss the infection, so you may need a repeat test. Not sure which test you need? Our Patient Care Team is available 24/7 on 020 7099 0955.

Who runs Natsal?

Natsal is led by researchers from UCL, the London School of Hygiene & Tropical Medicine, the University of Glasgow, the University of Cambridge, Örebro University Hospital and NatCen Social Research. It’s funded by the Wellcome Trust, with contributions from the Economic and Social Research Council and the National Institute for Health and Care Research.

How reliable are Natsal’s findings?

Natsal chooses people at random from across Britain, so its results broadly reflect the population, and people answer the most sensitive questions privately. Natsal-3 had a response rate of 57.7%. Like any survey, it relies on what people say about themselves.

When will the Natsal-4 results be published?

The first results are due at the end of November 2026.

Natsal gives the most detailed picture we have of sex in Britain. Its latest published results show the gap between men and women narrowing and Chlamydia peaking in young adults, and new results from Natsal-4 are due at the end of November 2026. Whatever the averages say, if you’ve had a new partner, a test is the only way to know you’re clear.

Book a Full Screen at a clinic near you or order a home test kit. Our Patient Care Team is available 24/7 on 020 7099 0955.

Not in the UK? Choose your country from the selector at the top of the page for local tests and prices.

This article originally appeared on 26 December 2014 and was last updated on 1 October 2026.

This article is general information and not a substitute for personal medical advice.

Sources

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2. Natsal, History of Natsal. https://www.natsal.ac.uk/about/history-of-natsal/
3. Natsal, Why does Natsal matter? https://www.natsal.ac.uk/about/why-does-natsal-matter/
4. Natsal, Natsal-3 key findings (survey carried out 2010 to 2012). https://www.natsal.ac.uk/natsal/wp-content/uploads/2023/03/Natsal-3-infographics.pdf
5. Natsal, Natsal-3 reference tables (survey carried out 2010 to 2012). https://www.natsal.ac.uk/natsal/wp-content/uploads/2023/03/Natsal-3-Reference-tables.pdf
6. Erens B et al., National Survey of Sexual Attitudes and Lifestyles 3: technical report, volume 1, November 2013. https://www.natsal.ac.uk/natsal/wp-content/uploads/2023/03/Natsal-3-technical-report.pdf
7. Natsal, Natsal-4. https://www.natsal.ac.uk/researchers/natsal-4/
8. Natsal, Natsal-4: methodology and questionnaires. https://www.natsal.ac.uk/researchers/natsal-4/methodology-questionnaires/
9. NHS, Help after rape and sexual assault, reviewed 6 November 2024. https://www.nhs.uk/live-well/sexual-health/help-after-rape-and-sexual-assault/
10. NHS, Sexually transmitted infections (STIs), reviewed 13 May 2024. https://www.nhs.uk/conditions/sexually-transmitted-infections-stis/
11. NHS, HIV and AIDS, reviewed 9 July 2025. https://www.nhs.uk/conditions/hiv-and-aids/
12. British Association for Sexual Health and HIV, Summary guidance on testing for sexually transmitted infections, 2023. https://www.bashh.org/_userfiles/pages/files/resources/bashh_summary_guidance_on_stis_testing_2023.pdf
13. British HIV Association, British Association for Sexual Health and HIV and British Infection Association, Adult HIV testing guidelines, 2020. https://bhiva.org/wp-content/uploads/2024/10/HIV-testing-guidelines-2020.pdf
14. British Association for Sexual Health and HIV, UK guidelines for the management of syphilis, 2024. https://bashh.org/_userfiles/pages/files/syphilis_2024.pdf