How Long After Sex Should I Get an STI Test in Australia?

This article is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Clinical guidelines are reviewed and updated over time — always confirm current advice with a qualified health provider. If you're experiencing severe pain, fever, or other urgent symptoms, seek immediate medical attention rather than relying on this article or at-home testing.

For chlamydia and gonorrhoea, the infections TestSmart tests for, wait at least 2 weeks after potential exposure before testing. Testing sooner can give a false negative even if you're infected. Here's why, and what to do if you're anxious to test sooner.

What Is a Window Period?

A window period is the time between when you're exposed to an infection and when a test can reliably detect it. During this period, the infection is present in your body but hasn't yet reached levels detectable by a lab test. If you test during the window period, you may get a negative result even if you're actually infected — a false negative.

This is why timing matters. Testing too early is one of the most common reasons for inaccurate STI results.

Window Periods by STI

The table below shows the recommended waiting time before testing for each infection, based on Australian sexual health guidelines and standard NAAT testing methods.

TestSmart currently offers testing for chlamydia and gonorrhoea. The guidance below focuses on these infections.

How Long After Sex to Test for Chlamydia and Gonorrhoea

The window period for both chlamydia and gonorrhoea is typically one to two weeks when using NAAT (nucleic acid amplification testing) — the method used by Australian accredited pathology laboratories including ACL, TestSmart's lab partner.

In practical terms: wait at least two weeks after a potential exposure before testing. Testing at the two-week mark gives reliable results for most people. If you test at one week and get a negative result but remain concerned, retesting at two weeks is reasonable.

Important: the two-week window applies to genital testing via urine sample. The same window period applies to throat and rectal swab testing. If you've had oral or anal sex and want to rule out throat or rectal infection, these sites need to be tested separately — genital testing alone will miss them.

What If I Need to Know Sooner?

There's no test that can reliably detect chlamydia or gonorrhoea within the first week of infection. If you've had a potential exposure and are anxious about your status, the most useful things you can do in the immediate short term are:

•       Use condoms with any partners until you're able to test

•       Avoid sexual contact if you develop any symptoms (discharge, pain, unusual odour)

•       Book your test for the two-week mark

Testing before two weeks is unlikely to give you a definitive answer and may create unnecessary anxiety if the result comes back negative — because it may not yet be meaningful.

I Had Sex Last Night — Should I Test Now?

No. Testing within 24–48 hours of potential exposure will not give you a useful result. Even the most sensitive NAAT tests cannot detect infection this early. Wait at least two weeks.

If you've been exposed to a known positive partner and are concerned, contact a sexual health clinic or your GP. In some circumstances a doctor may consider preventive treatment, but this is a clinical decision made in consultation with a doctor, not something that replaces testing.

What About Testing After a Condom Broke?

A broken condom is a common reason people seek STI testing. The same window periods apply — two weeks for chlamydia and gonorrhoea. There's no shortcut that gives you a meaningful result sooner.

If the encounter involved a person whose HIV status is unknown or positive, contact a sexual health clinic or emergency department promptly — within 72 hours — to discuss HIV post-exposure prophylaxis (PEP). PEP is a 28-day course of antiretroviral medication that can prevent HIV infection if started quickly enough. For chlamydia and gonorrhoea from a broken condom, wait two weeks, then test.

What If My First Test Is Negative but I'm Still Worried?

A negative result at two weeks is reassuring for chlamydia and gonorrhoea. If you tested at the two-week mark or later and got a negative result, and you haven't had any further potential exposures, that result is reliable.

If you're still concerned — for example, because you tested slightly before the two-week window, or because symptoms have developed since testing — retesting is reasonable. When in doubt, test again.

How Does At-Home Testing Fit Into This?

TestSmart's at-home kits are designed for asymptomatic screening — for people who want to check their status after a potential exposure, as part of a regular testing routine, or because a previous partner has disclosed a positive result.

The testing method is the same NAAT technology used in clinics and hospitals across Australia, processed by ACL Pathology (NATA-accredited). This means the window period guidance above applies equally to TestSmart tests as it does to clinic-based testing.

Once you've waited the recommended time, ordering is straightforward: complete a short health questionnaire, an Australian-registered GP reviews your responses and issues a referral, and your kit is delivered in discreet packaging. You collect your sample at home and return it using the prepaid mailer. Results are available in 3–4 business days.

Summary: When to Test After Sex

TestSmart offers at-home testing for chlamydia and gonorrhoea across Australia. No clinic visit, no collection centre required. Visit testsmart.com.au to get started.

TestSmart's testing and treatment pathways are reviewed by Australian-registered GPs and follow current Australian clinical guidelines. This article is general information only and does not replace individual medical advice — your circumstances, symptoms, and test results should always be discussed with your reviewing doctor.