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.

Getting an HIV test in St. Louis can be quick, free and private. You do not need to be sure about your risk, and you do not need a referral. This guide walks you through the process from start to finish.

It covers where free HIV testing in St. Louis is available, how to prepare, what happens during a visit, and what the results can mean. It also explains the different kinds of tests and the window periods the CDC publishes.

Why an HIV test is worth knowing about

The CDC recommends that everyone ages 13 to 64 get tested for HIV at least once as part of routine health care. The U.S. Preventive Services Task Force (USPSTF) similarly recommends screening for adolescents and adults ages 15 to 65. People with a higher chance of exposure may benefit from testing more often, and a clinician can help you decide how often.

Local numbers show why testing access matters here. The City of St. Louis Fast-Track Cities HIV Data page reports 108 new HIV diagnoses in St. Louis City in 2021, a rate of 36.0 per 100,000 people. The same page lists 143 new diagnoses in St. Louis County (15.0 per 100,000) and 633 in Missouri overall (10.0 per 100,000).

HIV is treatable. The CDC says that with treatment from a clinician, people with HIV can stay healthy for many years. HIV is not curable, but it is manageable. Testing is the first step toward care and toward prevention.

What you need before you go (materials checklist)

Testing does not require much preparation. Here is what can make the visit smoother.

A way to get there. The City Health Stop is downtown at 1520 Market St, Suite 1625, St. Louis, MO 63103.
A phone. You may want to call ahead, and you may want to save the clinic's number for results.
A few notes about timing. It helps to remember roughly when any possible exposure happened, because that affects which test makes sense.
A list of questions. Examples: which test will be used, when results arrive, and what happens if a result is reactive.
Time. A rapid test takes about 15 minutes at the City Health Stop, according to the City of St. Louis. Plan for a little longer for check-in and conversation.
Insurance information, only if the clinic asks. The City Health Stop says there is no cost and no ID is needed. Other clinics may ask for insurance or ID, so check when you call.

Step 1: Choose the kind of test that fits your situation

HIV tests look for different things in the body. Some look for antibodies, which are made by your immune system in response to HIV. Others look for an antigen called p24, or for the virus itself. The CDC describes three main types.

Antibody tests

Antibody tests look only for antibodies. Most rapid tests are antibody tests, and so are most home self-tests. The CDC says antibody tests can take 23 to 90 days to detect HIV after an exposure. The CDC also notes that antibody tests using blood from a vein can detect HIV sooner than tests using a fingerstick or oral fluid.

Antigen/antibody tests

These tests look for both antibodies and the p24 antigen. The CDC says an antigen/antibody test done in a lab on blood from a vein can detect HIV 18 to 45 days after an exposure. A rapid antigen/antibody test done on a fingerstick has a longer window, from 18 to 90 days, according to the CDC.

Nucleic acid tests (NAT)

A NAT looks for the virus itself. The CDC says a NAT can detect HIV 10 to 33 days after an exposure. NATs are not usually the first choice for routine screening. A clinician may consider one after a recent possible exposure, especially if there are early symptoms.

Test type	What it looks for	CDC window period
Antibody test (blood from a vein)	Antibodies	Can detect HIV 23 to 90 days after exposure, per the CDC
Antibody test (fingerstick or oral fluid, including rapid and self-tests)	Antibodies	Can take 23 to 90 days, and may detect HIV later than vein-blood tests, per the CDC
Antigen/antibody test (lab, blood from a vein)	Antibodies and p24 antigen	18 to 45 days, per the CDC
Antigen/antibody test (rapid, fingerstick)	Antibodies and p24 antigen	18 to 90 days, per the CDC
Nucleic acid test (NAT)	The virus itself	10 to 33 days, per the CDC

The window period is the time between an exposure and when a test can reliably show a result. A test taken inside the window may not show HIV even if an exposure did happen. This is why the CDC advises retesting after the window period if you test early. A clinician can tell you which test and which timing fit your situation.

Step 2: Pick a free testing site in St. Louis

City of St. Louis Health Stop Testing and Referral Center

The City of St. Louis Department of Health runs the Health Stop. This is the main free option in the city.

Address: 1520 Market St, Suite 1625 (first floor), St. Louis, MO 63103.
Phone: (314) 657-1584 for scheduling, results help and linkage to care. The Department of Health main line is (314) 612-5100.
Hours: Monday through Thursday, 9 a.m. to 12 p.m. and 1 p.m. to 4 p.m. It is closed on Fridays, from 12 to 1 p.m., and on city holidays.
Cost: The city page says, "There is no cost for this service, and no ID is necessary to receive the service."
Tests listed: HIV (fingerstick or blood draw), hepatitis C (fingerstick), gonorrhea and chlamydia (urine, mouth swab or rectal swab), and syphilis (blood or fingerstick).
Speed: Rapid tests take about 15 minutes. STI results take 5 to 7 business days, according to the city.

The city page says walk-ins are accepted, subject to availability. The CDC GetTested listing for this site says an appointment is required. Because those two sources differ, call (314) 657-1584 before you go to confirm.

You can read the details on the City of St. Louis Health Stop page.

Other places to ask about HIV testing

Several other St. Louis-area clinics list HIV testing. Costs and hours vary, so call first. You can compare them on our local testing list.

Planned Parenthood Great Rivers, Central West End Health Center, 4251 Forest Park Ave, St. Louis, MO 63108, (314) 531-7526. The CDC GetTested listing shows rapid HIV testing and blood-draw HIV testing, a sliding scale fee, and that an appointment is required.
CareSTL Health, Dr. Martin Luther King Health Center, 5471 Dr Martin Luther King Dr, St. Louis, MO 63112, (314) 367-5820. The CDC listing shows HIV blood-draw testing, a sliding scale fee, and that an appointment is required.
WashU Infectious Diseases, Village Square Clinic, 1 Village Square Shopping Center, Suite 1, Hazelwood, MO 63042, (314) 362-9098. WashU's 2024 news article says a CDC-funded expansion aims to offer walk-in testing at no or low cost in north St. Louis County. Service details were still being worked out when that article was published, so confirm by phone.
Saint Louis County Sexual Health Clinic, 4000 Jennings Station Road, St. Louis, MO, (314) 615-9736. WashU Infectious Diseases lists it as walk-in only and welcoming to everyone regardless of where they live or their insurance status. It lists STI prevention, testing and treatment. The listing does not show hours or cost, and does not specifically list HIV tests, so ask when you call.

You can also look up more sites on the CDC's GetTested locator, which lets you search by ZIP code.

Free HIV self-test kits

If you would rather test privately at home, the City of St. Louis says the Health Stop provides a free HIV self-test kit that uses an oral fluid swab. The city page also says kits can be ordered by mail through TakeMeHome.org. TakeMeHome.org says it offers free kits after a short eligibility screen. The page did not state the eligibility rules, so you will see them when you apply.

The CDC notes that self-tests are generally antibody tests, so the window period for antibody tests applies. If a self-test is reactive, the next step is a follow-up test with a clinician. If it is negative and your possible exposure was recent, the CDC advises retesting after the window period.

Step 3: Make the call or plan your walk-in

A short phone call can save you a trip. Here is what to ask.

Is it a walk-in, or do I need an appointment?
What are today's hours, and is there a cutoff for arriving?
Is there a cost, and what do I need to bring?
Which HIV test do you use, and is the result available the same day?
If a result is reactive, how do you arrange the next test and a visit with a clinician?

Remember that the City Health Stop is closed on Fridays and city holidays. Plan for Monday through Thursday.

Step 4: What to expect at the visit

Staff will explain the process, ask a few questions, and collect a sample. Here is what most visits look like.

Check-in. At the City Health Stop, no ID is required. Other sites may ask for details.
A brief conversation. A staff member may ask about the timing of any exposure and about your health. You can share as much as you are comfortable with. Questions are meant to pick the right test, not to judge.
The sample. This may be a fingerstick, an oral swab, or a blood draw from a vein. Sample type depends on the test.
The wait. For a rapid test, results typically take about 15 minutes at the City Health Stop. Lab-based tests take longer.
The result conversation. A staff member will share the result and talk through next steps. You can ask them to slow down or repeat anything.

You can also ask for other tests at the same visit. The City Health Stop lists hepatitis C, gonorrhea, chlamydia and syphilis testing alongside HIV testing.

Step 5: Understand what your result can mean

Results are described in careful terms because a single test is one piece of information. Here is how to read the common outcomes.

A non-reactive (negative) result

A non-reactive result means the test did not detect HIV in that sample. If your last possible exposure was within the window period for that test, a clinician may suggest testing again later. The CDC lists the window periods above. If you have ongoing exposure, a clinician can suggest how often to test.

A reactive (preliminary positive) result

A reactive result on a rapid test or self-test is a preliminary result. It means the test reacted, and it needs a follow-up test to confirm. It does not by itself confirm HIV.

The CDC describes a confirmation step using a lab testing approach. This typically includes an antigen/antibody test followed by a test that distinguishes HIV-1 from HIV-2. A nucleic acid test may be used if results do not agree. A clinician or testing staff member will arrange this, and the City Health Stop lists linkage to care among its services.

An unclear or inconclusive result

Sometimes a result is unclear. Staff may suggest repeating the test or using a different type, such as a NAT. This is a routine part of testing and does not point in either direction on its own.

Step 6: Plan your next steps

If a follow-up test is needed or HIV is confirmed

HIV treatment is prescribed by a clinician. The CDC says treatment can lower the amount of virus in the body to a level where tests no longer detect it, and that people who keep it that way do not pass HIV to sexual partners. This is often called undetectable equals untransmittable.

For help connecting to care in St. Louis, the City of St. Louis lists a Linkage to Care Intake Line at 314-356-0200. The Health Stop at (314) 657-1584 also offers linkage to care.

If you are not living with HIV

Ask a clinician about prevention options. These include PrEP, a medicine a clinician prescribes to lower the chance of getting HIV. The CDC also describes PEP, which is used after a possible exposure and needs to start as soon as possible, within 72 hours according to the CDC. If you think you had a recent exposure, contact a clinician or urgent care right away rather than waiting for a test.

Planned Parenthood Great Rivers and CareSTL Health both list PrEP navigation on their CDC GetTested listings. WashU Infectious Diseases mentions PrEP, PEP and doxy-PEP at its Village Square Clinic. Call to confirm availability. For general PrEP information, the Missouri Department of Health and Senior Services (DHSS) HIV, STI and Hepatitis program can be reached at 888-252-8045 or [email protected]. Its PrEP page links to the CDC's "Paying for PrEP" resource and does not describe a Missouri-specific payment assistance program.

Tips for a smoother visit

Call first. The city page and the CDC listing differ on appointments, so a quick call settles it.
Arrive early in the day. The city says walk-ins are subject to availability.
Ask which test is used. Knowing the test type helps you understand its window period.
Bring a partner or friend if it helps. Many people find the wait easier with company.
Ask for other tests. One visit can cover HIV, syphilis, chlamydia, gonorrhea and hepatitis C at the City Health Stop.
Write down the next step before you leave. This includes when to retest, who to call, and when results arrive.
Ask about privacy. The city describes Health Stop testing as confidential. You can ask any clinic how it handles your information.

Common mistakes to avoid

Testing once and stopping. A single test inside the window period may not show an exposure. Ask whether to retest.
Treating a reactive rapid test as final. It needs a follow-up test. Equally, a reactive result is not something to ignore.
Showing up on a Friday or at lunch. The City Health Stop is closed on Fridays and from 12 to 1 p.m. on other days.
Assuming every site has the same cost. The City Health Stop lists no cost. Other clinics use sliding scales or did not publish a price, so ask.
Skipping the question about timing. Telling staff roughly when an exposure happened helps them choose the right test.
Waiting for symptoms. The CDC notes that many people with HIV do not have symptoms for years. Testing is the only way to know your status.
Delaying care after a reactive follow-up test. Early contact with a clinician matters. The linkage line is there to help.

What if you are under 18?

Missouri law (RSMo 431.061) says a minor may consent for themselves to treatment in the case of venereal disease, and the statute states no minimum age. That section is about treatment. How a given clinic handles testing for minors can vary, so ask the clinic when you call. The Health Stop and other sites can explain their rules.

What to expect from your results: setting realistic expectations

No test is perfect, and results depend on timing, the type of test and how it was done. A rapid test can give a result in about 15 minutes, but it reports only whether the test reacted. Staff and clinicians can explain what a result suggests and what the next test would be. They are the right people to interpret it for your situation.

Most people who test find the process shorter and easier than they expected. The staff at the City Health Stop and other clinics hear every kind of question, and none of them are out of place.

Quick summary

Choose a test type that fits the timing of any exposure.
Pick a site, such as the City of St. Louis Health Stop, which lists no cost and no ID requirement.
Call to confirm hours and whether you need an appointment.
Take the test and ask about the result and next steps.
If a result is reactive, follow up with a confirmatory test and a clinician.
Ask about prevention and retesting.

To compare more options, use the CDC GetTested locator or call the City of St. Louis Department of Health at (314) 612-5100.

Free and Rapid HIV Testing in St. Louis