Chlamydia is tested with a simple urine sample or swab, and you can get results in as little as one day. The standard test is called a nucleic acid amplification test (NAAT), which detects the genetic material of the bacteria. It’s considered the gold standard by the World Health Organization and picks up about 94% of infections, making it highly reliable.
How the Test Works
A NAAT test amplifies tiny traces of chlamydia DNA in your sample so the lab can detect even small amounts of bacteria. This is the same type of technology behind PCR COVID tests. For chlamydia, it can be run on urine, vaginal swabs, rectal swabs, or throat swabs depending on where the infection might be.
The accuracy is consistently high across sample types. Studies show NAAT-based tests have about 94% sensitivity for cervical swabs, 94% for vaginal swabs, 95% for urine, and 93% for rectal swabs. Specificity sits at 99%, meaning false positives are extremely rare. If the test says you have chlamydia, you almost certainly do.
What to Expect During Sample Collection
For a urine test, you’ll provide a “first-catch” sample, which means the first stream of urine rather than a midstream sample. You’ll be asked to pee directly into a cup and collect roughly the first 30 mL. Two important details: don’t urinate for at least one hour before the test, and don’t clean your genital area beforehand. Both of these steps help ensure enough bacteria end up in the sample.
For a swab test, a clinician uses a soft swab to collect cells from the cervix, vagina, urethra, rectum, or throat. Vaginal swabs can also be self-collected, which many clinics and home testing kits now offer. The process takes seconds and is generally painless, though rectal and cervical swabs can cause brief discomfort.
When to Get Tested After Exposure
Chlamydia needs time to build up enough in your body for a test to detect it. Testing too soon after exposure can produce a false negative. The minimum wait is about one week, which catches most infections. Waiting two weeks catches nearly all of them. If you test at one week and get a negative result but still have concerns, retesting at the two-week mark gives you more certainty.
Keep in mind that chlamydia often causes no symptoms at all, which is why routine screening matters so much. You can carry the infection for months without knowing.
Who Should Get Screened Routinely
The CDC recommends annual chlamydia screening for all sexually active women under 25. Women 25 and older should also be screened annually if they have a new sex partner, more than one partner, or a partner who has an STI. Adolescents and others with higher-risk behaviors may benefit from screening more often than once a year.
For men, the evidence doesn’t support blanket routine screening the way it does for women, but screening is recommended in settings where chlamydia rates are high, such as STI clinics and correctional facilities. Men who have sex with men should be screened at least annually, and more frequently based on risk.
Extragenital Testing
A standard urine test or genital swab only detects chlamydia at those sites. If you’ve had oral or anal sex, the infection can live in your throat or rectum without showing up on a urine test. Rectal and throat swabs use the same NAAT technology and are the only way to catch infections at those sites. If your provider doesn’t ask about your sexual practices, it’s worth bringing it up so they can order the right tests.
Home Testing vs. Clinic Testing
Home chlamydia test kits are widely available and use the same NAAT technology as clinic-based tests. FDA-approved home kits report 95 to 99% accuracy when used correctly. You typically collect a urine sample or vaginal swab at home and mail it to a lab.
The catch is that accuracy depends heavily on following the instructions precisely. In a clinic, trained staff handle collection in a controlled environment, eliminating variables like contamination, improper technique, or temperature changes during shipping. Sample collection mistakes are the most common source of error with home kits. If you go the home testing route, stick with an FDA-approved kit and follow the instructions exactly, especially the timing around urination.
How Long Results Take
Lab-based NAAT results are typically ready within one day. Some clinics and newer point-of-care tests can return results in 90 minutes or less, though these rapid options aren’t available everywhere. If you test through a home kit, factor in shipping time to the lab on top of the processing time, which usually means a few days to a week total.
A positive result is straightforward to treat with antibiotics, and your provider will likely recommend that any recent sexual partners get tested and treated as well. Retesting is generally recommended about three months after treatment to make sure the infection hasn’t returned, since reinfection rates are high.