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How do HIV tests work and what's involved?

What's involved in testing for HIV?

  • There are plenty of places which offer free HIV testing – you can find your nearest provider either by searching online or asking a healthcare professional. 
  • Testing for HIV is a simple and pain-free process. It involves giving a small sample of blood or oral fluid.
  • Your results will be confidential and the healthcare provider will be able to explain the process and answer any questions you have. They are there to help you. 
  • HIV tests are very reliable. Some HIV tests will give a result within 20 minutes and others are sent to a lab so it may take a few weeks to get your results. 

It is really common to feel a little worried about going for an HIV test, but making the decision to test is the best thing you can do for your health. The process is quick, painless, confidential and almost always free.

Where can I get an HIV test? 

Depending on where you are in the world, there are a number of places that you can get tested for HIV. The best first step is to search online for "HIV testing”, plus your location. This will generally give you a good idea of where to go, or at least give you a starting point.

If you have limited internet access, it’s always worth asking local sexual health charities or health professionals what is available in your area. They should be able to direct you to somewhere where you can test for free. The image below has some examples of the types of places that might offer HIV testing.

The healthcare worker – there to help you!

Before you test, your healthcare worker will talk to you about your sexual health and why you’ve decided to test. This is to help them understand your situation so they can offer you the best services and advice.

Remember, the healthcare professional is not there to judge you. There will be nothing you can say that they haven’t heard before – so be honest with them, and ask as many questions as you want. That’s what they’re there for.

You should never feel pressured to test. The results will be completely confidential but you should only go through with it if you want to.

What happens when you go for a test?

Normally, testing involves taking a small sample of blood from your finger or your arm, or an oral swab. This is where you rub the testing pen along your gums to collect cells from your mouth.

How long it takes for HIV test results to come back will depend on the type of test you are taking. If you’re taking a rapid test, you will be given your results within 20 minutes. Other types of tests will be sent to a laboratory and it may take between a few days and a few weeks for you to receive a final result.

Tests these days are very reliable, but if your result comes back positive, you should have a second confirmatory test to double check your result. If this is also positive, you will get an HIV diagnosis, after which you can start treatment.

Remember, HIV treatment these days is very effective and people with HIV can live long and healthy lives just like anyone else.

How do HIV tests work?

There are a variety of different HIV tests and your healthcare worker should explain which test you are using and how you will get your result.

HIV antibody tests (also called third generation tests)

When you become infected with HIV, your body will start to produce specific antibodies (proteins that attach to the virus to try and destroy it). An HIV antibody test looks for these antibodies in your blood, oral fluid or urine. If these antibodies are found, it means that your body is reacting to an HIV infection and that you have HIV.

This test is only accurate three months after exposure, because this is how long it takes your body to produce enough antibodies for it to show up in a test. It usually takes a few days to a few weeks to get the results back from this type of test.

Combined antigen/antibody tests (also called fourth generation HIV tests)

Fourth generation tests look for HIV antibodies as well as something called p24 antigens. The p24 antigens are part of HIV itself. You will have a lot of these in your blood in the first few weeks after infection.

Fourth generation tests can reliably detect HIV from one month after you have been infected. It usually takes a few days to a few weeks to get results back for this type of test.

Rapid HIV tests

Rapid tests give results in just 20 minutes, so results can now be given on the spot at many healthcare centres. Most test for HIV antibodies by taking a prick of blood from your finger. These tests are only accurate three months after exposure. If you get a positive result, the healthcare professional will double-check this with a second test.


HIV self-testing offers the convenience of taking a test in the comfort of your own home. Unfortunately, self-testing hasn’t been approved everywhere, so check online to see if it is available where you are.

If you do order a self-testing kit, check that the kit has been approved with a ‘CE’ (Europe) or FDA (USA) mark on it. These tell you that the tests are regulated and will work properly. Follow the instructions that come with your kit and you should get a result in 15 – 20 minutes.

A positive result on a self-test kit isn’t enough to know for sure if you have HIV, so if you do get a positive result it must be confirmed by a healthcare worker. They will also ensure that you get the necessary follow-up care with treatment and support with counselling. 

Self-tests can be more convenient for some people and they allow you privacy while you get your results. But some people prefer to see a professional; that way they can get immediate support and advice on the next steps.

Read on to find out: What happens after an HIV test and getting the results?

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Photo credit: ©AVERT by Corrie Wingate


Last full review: 
06 June 2019
Next full review: 
06 June 2021
Last updated:
24 February 2021
Last full review:
06 June 2019
Next full review:
06 June 2021