How it works
The condom collects semen when the penis ejaculates, so sperm cannot enter the vagina. Because it also blocks contact with body fluids and reduces skin-to-skin contact, it lowers the risk of passing on many STIs, including HIV.
People who want protection from STIs as well as pregnancy, often alongside another method.
How effective is it?
Typical use
87%
In real life about 13 in 100 people get pregnant in a year with typical use.
Perfect use
98%
About 2 in 100 when used exactly as directed every time.
About 98% effective with perfect use every time
See how it ranks against every method in the effectiveness chart.
How to use it
Buy condoms from a pharmacy or shop, or get them free from many sexual health clinics; check the expiry date and look for a recognized safety mark.
Open the packet carefully (not with teeth or scissors), pinch the tip to squeeze out air, and roll the condom all the way down the erect penis before any genital contact.
Use water-based or silicone-based lubricant if needed; oil-based products such as petroleum jelly, baby oil or massage oil can damage latex condoms.
After ejaculation, hold the base of the condom while withdrawing before the penis goes soft, then throw it away in a bin. Use a new condom every time.
If a condom breaks or slips off, consider emergency contraception and an STI test.
Pros and cons
Advantages
- Lowers the risk of STIs, including HIV, as well as pregnancy
- No hormones and no effect on periods or fertility
- Easy to buy without a prescription and often free from clinics
- Only used when you have sex
- Can be combined with another method, such as the pill or an IUD, for extra protection
- Latex-free options are available for people with a latex allergy
Disadvantages
- Less effective than long-acting methods, because mistakes in use are common
- Has to be put on correctly every time, which can interrupt sex
- Can split, tear or slip off, especially if the wrong size or lubricant is used
- Some people find it reduces sensation
- Should not be used together with an internal condom, as friction can make both fail
Effect on periods: No effect on periods.
Possible side effects
- Usually none
- Irritation or an allergic reaction in people sensitive to latex
- Irritation from spermicide-coated condoms in some people
Who it may not suit
A clinician checks your medical history before you start. This list is not complete.
May not be suitable if
- You or your partner are allergic to latex (use polyurethane or polyisoprene condoms instead)
- Keeping an erection while putting on a condom is difficult
- A pregnancy would be very risky for your health and you want a more effective method on its own
Get medical help if
- A condom broke or slipped off and you want emergency contraception (sooner is better)
- You notice unusual discharge, sores, pain when peeing or other signs of an STI
- You have itching, swelling or a rash after using condoms, which may be an allergy
Frequently asked questions
How effective are condoms at preventing pregnancy?
Used perfectly every time, about 2 in 100 people get pregnant in a year. With typical use, which includes mistakes like putting it on late, the figure is about 13 in 100.
Do condoms protect against STIs?
Yes. Male and internal condoms are the only contraceptive methods that also lower the risk of STIs, including HIV. They protect less well against infections spread by skin-to-skin contact, such as herpes and genital warts, because they don't cover all skin.
What should I do if a condom breaks?
If you are not using another method, consider emergency contraception as soon as possible; a pharmacist or clinic can advise. It is also worth getting an STI test, and in some cases a clinic may offer HIV post-exposure prevention (PEP), which needs to start within 72 hours.
Can I use oil or Vaseline with a condom?
Not with latex condoms. Oil-based products such as petroleum jelly, baby oil, lotions and some vaginal creams weaken latex and can make it break, so use a water-based or silicone-based lubricant instead.
Should I use two condoms for extra protection?
No. Wearing two condoms, or using a male condom together with an internal condom, causes friction that makes them more likely to tear or slip. Use one condom correctly each time.
Sources
Reviewed 1 November 2026. We link to the guidance itself so you can check it.