Can you get HIV from oral sex?

Very unlikely. The risk of getting HIV from oral sex is much lower than from vaginal or anal sex, but it isn’t zero if the partner with HIV doesn’t have an undetectable viral load.

• Giving oral sex to someone with a penis: this carries a very low risk, which rises if semen or pre-cum gets into your mouth. Almost all reported cases involved ejaculation in the mouth.
• Receiving oral sex: this is thought to be an extremely low risk. There are no reliable reports of HIV passing from a mouth to the genitals.
• Oral sex on a vagina: a very low risk. Only a handful of cases have ever been reported, and experts doubt how reliable they are.
• Rimming (oral sex on the anus): little to no risk of HIV.

The risk goes up if:

• the partner with HIV isn’t on treatment, or has a high viral load
• they ejaculate in your mouth
• you have bleeding gums, mouth ulcers or cuts in your mouth
• you have a sore throat, a throat infection or another STI

Even then, the risk from oral sex stays very low compared with other types of sex. Read more in “How much saliva is needed to transmit HIV?”

People with HIV who take effective treatment and have an undetectable viral load cannot pass HIV on through sex. This is known as U=U, or undetectable equals untransmittable.

With treatment, most people with HIV can keep the virus under control. In England, 98% of people on HIV treatment have the virus suppressed. Read more in “Should I wear a condom if my HIV viral load is undetectable?”

HIV is a virus that damages the immune system. There were 3,043 new HIV diagnoses in the UK in 2024.

HIV is passed on through blood, semen (including pre-cum), vaginal fluid, anal mucus and breast milk, but not through sex when the person with HIV has an undetectable viral load. The main ways it spreads are:

• anal or vaginal sex without a condom
• sharing needles or other injecting equipment
• from a mother to her baby during pregnancy, birth or breastfeeding

Receptive anal sex carries the highest risk, because the lining of the rectum is thin and HIV can pass through it. Without treatment, the estimated risk from a single act of receptive anal sex is around 1.4%, and from vaginal sex around 0.04% to 0.08% in countries like the UK. For oral sex, the risk is too low to put a precise figure on. Read more in “How likely am I to get HIV based on the act?”

PEP (post-exposure prophylaxis) is emergency HIV medicine. It has to be started within 72 hours of exposure, and ideally within 24 hours.

UK guidelines don’t recommend PEP after oral sex, even with a partner who has HIV, because the risk is so low. It may be considered only in extreme cases, for example if the partner caught HIV very recently and there are ulcers or injuries in the mouth.

PEP may be recommended after anal or vaginal sex with a partner whose HIV isn’t controlled by treatment, and sometimes after anal sex with a partner whose HIV status you don’t know. If you think you need it, get urgent medical care straight away. Read more in “What is PEP and how does it work?”

While HIV is rare, other STIs pass on through oral sex much more easily, including:

• Gonorrhoea
• Chlamydia
• Syphilis
• Herpes
• HPV, although catching genital warts through oral sex is rare

Infections in the throat often cause no symptoms, so testing is the only way to know. Using a condom on a penis, or a dental dam (a thin latex or plastic square) over the vagina or anus, lowers the risk. Read more in “What is an oral sexually transmitted infection?”

To lower your risk of HIV and other STIs from oral sex:

• Use condoms and dental dams.
• Avoid oral sex if you have bleeding gums, mouth ulcers or a sore throat.
• Get tested regularly if you have new or casual partners.
• If you’re at higher risk of HIV, for example if you have sex without condoms with partners whose HIV isn’t controlled, ask about PrEP. Oral sex on its own isn’t usually a reason to take it.

HIV tests need time to give a reliable result. A fourth-generation lab blood test is reliable from 45 days after a possible risk, and a rapid or self-test from 90 days. You can test sooner, but you may need to repeat the test. Tests for other STIs, like Gonorrhoea and Chlamydia, can pick up an infection from about 2 weeks after sex.

Better2Know offers:

• HIV 4th Generation: a blood test for HIV from 28 days after sex, with results in 1 day. UK guidance gives a window period of 45 days for this type of test, so if you test before then and the result is negative, you’ll need a repeat test. You can book it at one of our clinics or order an HIV home test kit.
• Oral Screen home test: tests a throat swab and a urine sample for Chlamydia and Gonorrhoea, and a blood sample for Syphilis, Herpes 1 and Herpes 2, from 14 days after sex (28 days for Herpes), with results in 2 days. A Syphilis test in the first 3 months after sex can miss the infection, so you may need a repeat test.
• Full Screen: tests for 7 infections, including HIV, Syphilis, Chlamydia and Gonorrhoea, from 28 days after sex, with results in 3 days (5 days for the home test).

Not sure which test you need? Our Patient Care Team is available 24/7 on 020 7099 0955.

Can you get HIV from swallowing semen?

The risk is very low, but ejaculation in the mouth is the main factor in the few reported cases of HIV from oral sex. The risk is higher if you have bleeding gums or mouth ulcers.

Can you get HIV from kissing?

No. You can’t get HIV from kissing, hugging or shaking hands.

Should I get tested after oral sex?

If you’re worried, yes. HIV is very unlikely, but other STIs are common after oral sex, and testing is the only way to know. Read more in “I had unprotected oral sex. Should I get tested?”

The risk of getting HIV from oral sex is very low, and there’s no risk at all from a partner with an undetectable viral load. But other STIs, like Gonorrhoea, Chlamydia, Syphilis and Herpes, spread much more easily through oral sex.

If you’re worried, get tested. Book an HIV 4th Generation test at a clinic near you, or order an Oral Screen home test to check for other STIs. 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 10 June 2022 and was last updated on 30 September 2026.

Medical review. This article was medically reviewed by Dr Steve Chapman, Doctor with a wealth of clinical experience in the field of STIs, on 16 July 2025. It is general information and not a substitute for personal medical advice.

Sources

1. aidsmap, Oral sex and the risk of HIV transmission. https://www.aidsmap.com/about-hiv/oral-sex-and-risk-hiv-transmission
2. Terrence Higgins Trust, Oral sex. https://tht.org.uk/sexual-health/improving-your-sexual-health/oral-sex
3. Terrence Higgins Trust, How HIV is transmitted. https://www.tht.org.uk/hiv/about-hiv/how-hiv-transmitted
4. NHS, HIV and AIDS, reviewed 9 July 2025. https://www.nhs.uk/conditions/hiv-and-aids/
5. Centers for Disease Control and Prevention, How HIV spreads, reviewed 25 November 2024. https://www.cdc.gov/hiv/causes/index.html
6. Centers for Disease Control and Prevention, HIV risk and prevention estimates, 5 November 2024. https://www.cdc.gov/hivpartners/php/riskandprevention/index.html
7. Boily MC et al. Heterosexual risk of HIV-1 infection per sexual act: systematic review and meta-analysis of observational studies. Lancet Infectious Diseases, 2009;9(2):118-129. https://researchonline.lshtm.ac.uk/id/eprint/5517
8. British HIV Association, BHIVA encourages universal promotion of Undetectable equals Untransmittable (U=U), 30 November 2018. https://bhiva.org/BHIVA-encourages-universal-promotion-of-U-U/
9. British Association for Sexual Health and HIV and British HIV Association, UK guideline for the use of HIV post-exposure prophylaxis, 2021, amended 2023. https://bhiva.org/wp-content/uploads/2024/10/PEP-guidelines.pdf
10. British Association for Sexual Health and HIV and British HIV Association, Guidelines on the use of HIV pre-exposure prophylaxis (PrEP), 2025. https://bhiva.org/wp-content/uploads/2025/07/2025-PrEP-guidelines.pdf
11. NHS, Who can and cannot take pre-exposure prophylaxis (PrEP), reviewed 10 March 2023. https://www.nhs.uk/medicines/pre-exposure-prophylaxis-prep/who-can-and-cannot-take-pre-exposure-prophylaxis-prep/
12. UK Health Security Agency, HIV testing, PrEP, new HIV diagnoses and care outcomes for people accessing HIV services: 2025 report, updated 15 April 2026. https://www.gov.uk/government/statistics/hiv-annual-data-tables/hiv-testing-prep-new-hiv-diagnoses-and-care-outcomes-for-people-accessing-hiv-services-2025-report
13. NHS, Gonorrhoea, reviewed 16 December 2024. https://www.nhs.uk/conditions/gonorrhoea/
14. NHS, Chlamydia, reviewed 24 October 2024. https://www.nhs.uk/conditions/chlamydia/
15. NHS, Syphilis, reviewed 17 March 2026. https://www.nhs.uk/conditions/syphilis/
16. NHS, Genital herpes, reviewed 27 June 2023. https://www.nhs.uk/conditions/genital-herpes/
17. NHS, Genital warts, reviewed 10 July 2023. https://www.nhs.uk/conditions/genital-warts/
18. 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
19. British Association for Sexual Health and HIV, UK guidelines for the management of syphilis, 2024. https://bashh.org/_userfiles/pages/files/syphilis_2024.pdf