The honest answer is that it depends on who you are and the kind of sex you're having. As a rough rule of thumb, both US and UK guidance land in a similar place. If you're sexually active and not in a closed, mutually exclusive relationship, get a full STI check at least once a year and after a new partner. If you have several partners, test every 3–6 months. Below is what the official guidance actually says.
Quick answer: how often should I get tested?
- At least once, everyone: HIV (ages 13–64) and hepatitis C (all adults) [1] [4].
- Every year: chlamydia and gonorrhea if you're a woman under 25, or older with new or multiple partners [1]. In the UK, anyone sexually active is advised to test yearly and after a partner change [5].
- Every 3–6 months: if you're a man who has sex with men and you have multiple or anonymous partners [1], or (UK guidance) if you use PrEP, have had more than 10 partners in a year, or have had a bacterial STI in the past year [5].
- Any time you have symptoms, or a partner tells you they've tested positive. Don't wait for your next routine test.
US guidance (CDC)
These are the CDC's current testing recommendations, summarised from its public testing page and the 2021 STI Treatment Guidelines [1] [2].
| Who | What and how often | Source |
|---|---|---|
| Everyone aged 13–64 | HIV at least once. | CDC |
| All adults 18+ | Hepatitis C at least once in a lifetime. Retest periodically if you have ongoing risk factors. | CDC |
| Sexually active women under 25 | Chlamydia and gonorrhea every year. | CDC |
| Women 25+ with a new partner, multiple partners, or a partner with an STI | Chlamydia and gonorrhea every year. | CDC |
| Gay, bisexual and other men who have sex with men | Syphilis, chlamydia and gonorrhea at least once a year. HIV at least once a year. Every 3–6 months if you have multiple or anonymous partners. | CDC |
| Anyone at higher risk of HIV (e.g. multiple partners, shared injection equipment) | HIV at least once a year. | CDC |
| Pregnant people | Syphilis, HIV, hepatitis B and hepatitis C early in pregnancy, plus other tests depending on risk. | CDC |
| Transgender and gender-diverse people | Screening based on your anatomy and the kind of sex you have. Consider syphilis at least once a year depending on exposure. | CDC |
| Anyone who has oral or anal sex | Ask about throat and rectal swabs. A urine test alone can miss infections at those sites. | CDC |
The CDC also says most sexually active adults should be tested for syphilis based on where they live, because syphilis rates differ a lot by area. Ask a clinician whether that applies to you [1].
UK guidance (BASHH / UKHSA)
UK sexual health clinics follow British Association for Sexual Health and HIV (BASHH) guidance. Its 2023 summary sets out how often people without symptoms should test [5]:
| Your situation | How often |
|---|---|
| One long-term partner, and you're only having sex with each other | Test at the start of the relationship. |
| Sexually active | Once a year, and after each new partner (no more often than every 3 months). |
| Higher risk: PrEP users, more than 10 partners in the past year, multiple or anonymous partners since your last test, chemsex, or a bacterial STI in the past year | Every 3 months. |
Source: BASHH Summary Guidance on Testing for STIs, 2023, citing UKHSA (2022) [5]. The NHS says you don't usually need a GP referral for a sexual health clinic, you don't have to give your real name, and your visit won't be shared with your GP unless you ask [6].
Why test if you feel fine?
Many STIs have no symptoms, so you can have one without knowing and pass it on. Testing is the only way to know for sure [6]. Chlamydia and gonorrhea are usually easy to treat once found, but if they're left untreated they can cause longer-term problems.
Timing matters: don't test too early
Every test has a window period, the time after exposure before it can reliably pick up an infection. Test too soon and you can get a false negative. The NHS says that if you don't have symptoms, it's best to wait about 7 weeks after unprotected sex for a full screen [6]. Some tests need longer, though, like syphilis and some HIV tests. Our STI window period chart breaks it down test by test.
One big exception: if you think you were exposed to HIV in the last 72 hours, don't wait for a test. Go to a sexual health clinic or A&E/ER now and ask about PEP. It has to be started within 72 hours to work [7].
Hard to remember when you last tested? BodCount logs your STI tests and results on your iPhone, shows when you last tested, and flags partners from the relevant window if a result comes back positive. See how the STI test tracker works.
Track your tests in BodCountSources
- CDC. Getting Tested for STIs (last updated March 2026).
- CDC. STI Screening Recommendations, Sexually Transmitted Infections Treatment Guidelines, 2021.
- CDC. Getting Tested for HIV.
- CDC. Recommendations for Hepatitis C Screening Among Adults — United States, 2020. MMWR Recommendations and Reports.
- BASHH Clinical Effectiveness Group. BASHH Summary Guidance on Testing for Sexually Transmitted Infections, 2023 (testing frequencies from UKHSA, 2022).
- NHS. Sexually transmitted infections (STIs).
- CDC. Post-Exposure Prophylaxis (PEP).
Frequently asked questions
How often should I get tested for STIs?
If you're sexually active and not in a mutually exclusive relationship, at least once a year and after each new partner is a good baseline. If you have multiple or anonymous partners, the CDC suggests every 3–6 months for men who have sex with men, and UK guidance suggests every 3 months for people at higher risk. Test any time you have symptoms.
Should I get tested after every new partner?
UK guidance (BASHH, citing UKHSA) recommends testing annually and after a partner change, but no more often than every 3 months if you have no symptoms. Remember window periods, since testing too soon after sex can miss an infection.
I'm in a monogamous relationship. Do I still need to test?
UK guidance suggests testing at the start of a mutually exclusive relationship. After that, routine testing isn't usually needed unless something changes. The CDC still recommends everyone aged 13–64 has an HIV test at least once, and all adults a hepatitis C test at least once.
Does a urine test check for everything?
No. A urine test or vaginal swab usually checks for chlamydia and gonorrhea at the genitals. HIV, syphilis and hepatitis need a blood test, and if you have oral or anal sex you may need throat or rectal swabs. Ask the clinic what you're being tested for.
How soon after sex can I get tested?
It depends on the infection and the test. The NHS suggests waiting about 7 weeks after unprotected sex for a full screen if you have no symptoms. Chlamydia and gonorrhea can be tested after about 2 weeks, and some HIV and syphilis tests need up to 90 days. If you're worried about HIV exposure in the last 72 hours, ask about PEP straight away.
Is this medical advice?
No. This is general information, not medical advice. Talk to a clinician or sexual health clinic about your own situation.