This page is general health information, not medical advice. It cannot tell you whether you have an infection. A clinician can, and the testing options on this site are a good place to start.

The short answer is that it depends on the infection and on the test. Some infections show up on a test within days. Others take weeks. And if you have symptoms, or a partner has told you they tested positive, you do not need to wait out any window before talking to a clinician.

This guide walks you through how to work out your timing, step by step. It is written for people in Orlando and Orange County, and it focuses only on the "when" question. For a full rundown of clinics and costs, see our guide to STD testing in Orlando, where to get tested and what it costs.

First, what a window period means

A window period is the time between an exposure and the point when a test can reliably pick up an infection. A test taken inside that window can come back negative even if an infection is present. That is why timing matters when you think about how long after sex to test for STD infections.

The window is different for each infection. It is also different for each type of test. A clinician can tell you which test fits your situation.

What you will need

The date of the sex or exposure you are thinking about, as best you remember it.
A short list of any symptoms, with the date each one started.
Whether you have had other partners since then, and whether you plan to have sex before your results come back.
A photo ID. The Florida Department of Health in Orange County says its STD clinic requires one.
A way to pay, or a question ready about fees. The county says clinic fees range from $20 and up, with a sliding scale after an eligibility screening.
Your phone, to call ahead and confirm hours.

Step-by-step: how to time your test

Step 1: Check for symptoms or a known exposure

Start here, because it changes everything else. Symptoms can include unusual discharge, burning when you urinate, sores, bumps, a rash, pelvic pain or pain during sex. Many infections cause no symptoms at all, so a lack of symptoms is not a reason to rule anything in or out.

If you have symptoms, or a partner tells you they have an STI, contact a clinic now. A clinician can decide what to test for and whether to treat based on your exposure. You do not have to wait for a window period to pass before asking.

Step 2: Ask whether it has been under 72 hours

Some options only work soon after sex. The CDC says post-exposure prophylaxis for HIV (PEP) must be started within 72 hours of a possible exposure. Miracle of Love in Orlando says the same on its Test & Treat page, and lists low cost PEP. Its executive office is at 1301 W Colonial Dr, Ste 201, and the phone is (407) 843-1760.

The CDC also issued guidance in 2024 on doxycycline taken after sex (doxy-PEP) for some groups at higher risk of bacterial STIs. It is also time-sensitive. It is something a clinician prescribes, and only after a conversation about whether it fits you. If it has been less than three days, call a clinic first and ask about both.

Step 3: Match your timing to the infection

Here is what the CDC publishes, infection by infection.

HIV. The CDC lists window periods by test type:

A nucleic acid test (NAT) can usually detect HIV 10 to 33 days after exposure.
An antigen/antibody test done on a lab blood draw can usually detect it 18 to 45 days after exposure.
An antigen/antibody test done on a finger prick can take longer, 18 to 90 days.
Antibody tests, including home self-tests, can take 23 to 90 days.

That is a wide range, so ask which test the clinic is using. If you test early and the result is negative, the CDC advises testing again after the window for that test has passed.

Syphilis. The CDC says the first symptom, often a painless sore, shows up anywhere from 10 to 90 days after infection, with an average of 21 days. Blood tests can be negative early on. If your exposure was recent, a clinician may suggest a repeat test later.

Chlamydia and gonorrhea. The CDC does not publish a single waiting time that applies to everyone for these tests. Rather than guess a number, tell the clinician the date of your exposure and ask when they would test, and whether they would repeat the test later. Both are curable with treatment from a clinician.

Herpes, HPV and other infections. Timing and testing differ a lot for these, and the right approach depends on symptoms and the type of test. A clinician can explain what is and is not useful for you. Remember that herpes and HPV are not curable, but both are manageable, and HIV is treatable.

Step 4: Pick a testing date and a backup date

Many people find a two-visit plan easiest. The first visit is for the earliest useful test, or for care if you have symptoms. The second is for a repeat once the longest relevant window for your situation has passed.

For example, if a clinician uses an HIV lab antigen/antibody test, the CDC window of 18 to 45 days suggests when a follow-up could make sense. Your clinician may choose a different schedule, and theirs is the one to follow.

Step 5: Choose where to go and call ahead

Orlando has several options. Hours and walk-in rules change, so a quick call saves a trip.

Florida Department of Health in Orange County STD Clinic, 832 West Central Blvd, Orlando, FL 32805, 407-858-1400. The county page lists walk-in service, first come first served, Monday to Friday from 7:30 a.m. to 4 p.m., closed 12 to 1 p.m. Other county pages show different hours, so call to confirm. The clinic says results take about one week and are given in person or by coded text with signed consent.
The Center Orlando, 942 N Mills Ave. Its testing page lists walk-in only testing, with HIV and hepatitis C at $0, syphilis at $15, and chlamydia and gonorrhea at $50. Check its page for current hours and prices.
Miracle of Love lists HIV and STI screenings and says it does not perform gonorrhea or chlamydia swabs, so confirm which tests are offered before you go.
Hope & Help Center of Central Florida is in Winter Park, 4122 Metric Dr, #800, and serves the Orlando area. Its page lists testing as free, with no appointment necessary, and the phone is (407) 645-2577.

You can compare more places on our list of Orlando testing locations. The Orange County health department's Area 7 HIV/AIDS Program page also offers a free at-home HIV test kit order. It does not state eligibility on the page, so check the details with the program.

Step 6: Keep a record and plan for the days in between

While you wait for a window to pass or for results, you can use condoms or other barriers and talk with partners about testing. Write down your test date, the type of test and the date you were told to return. That record helps a clinician pick up where you left off.

Tips that make the timing easier

Tell the clinician your exposure date plainly. It is the most useful detail you can give.
Ask, "Which test are you using, and when should I repeat it?" This one question covers most of the timing confusion.
If you were treated for chlamydia or gonorrhea, the CDC recommends retesting about three months after treatment, because repeat infections are common.
If you are pregnant, tell the clinician. Florida Administrative Code Rule 64D-3.042 calls for STD testing at the first prenatal exam and again at 28 to 32 weeks.
If you are a minor, Florida Statute s. 384.30 says parental consent is not required for STD examination or treatment, and that the visit is confidential.

Common mistakes to avoid

Treating one early negative as the final word. A result inside a window period can change on a later test.
Waiting out a window when you have symptoms. Symptoms are a reason to call now.
Missing the 72-hour mark. PEP and doxy-PEP are time-sensitive, so call a clinic as early as you can.
Skipping the follow-up. A second test is part of the plan, not a sign something went wrong.
Relying on a number from a social post. Windows vary by test. Use the CDC figures above and your clinician's advice.
Assuming the clinic is open. Hours differ between sources, so call first.

What to expect from results

A negative result taken after the right window period suggests that a test did not find that infection. It may not rule out an exposure that was very recent, and no test is perfect. A clinician can tell you how to read your result in light of your exposure date.

A positive result is something to discuss with a clinician. Bacterial STIs and trichomoniasis can be cured with treatment from a clinician. HIV and herpes are not curable, though both can be managed with care from a clinician. Florida requires clinicians and labs to report some infections, such as chlamydia, gonorrhea, syphilis and HIV, to the health department, according to Florida Statute s. 381.0031 and Rule 64D-3.029.

Testing is common in Orange County. The Florida Department of Health's FLHealthCHARTS reported a 2025 chlamydia rate of 516.7 per 100,000 people in Orange County, compared with 410.8 statewide. Getting tested is a routine part of looking after your health.

Next step

Write down your exposure date, then call the clinic you picked. Ask which test they would use and when to come back. That one call settles most questions about how long after sex to test for STD infections.

How Long After Sex Should You Wait to Get Tested?