Lateral flow tests identify people who have COVID-19 but don't have symptoms, so that they can self-isolate and avoid spreading the virus to others.
If you do have symptoms, you need to self-isolate and order a PCR test, which is a different type of test.
Previous government advice was to take a lateral flow test twice a week. This advice has now been updated, recommending that people take a lateral flow test before 'high risk' situations, such as mixing with people indoors or in crowded spaces.
You should also take a lateral flow test before visiting someone who may be at a higher risk of developing severe illness.
It's worth taking lateral flow tests even if you've received your vaccinations and your booster, as you can still spread the virus even if you've been vaccinated.
There are a number of ways you can get hold of lateral flow tests. You can order them to your home on the GOV.UK website.
You can also pick up tests from many local pharmacies or from local test sites. You can find your closest pharmacy or test side offering lateral flow tests on the NHS website.
Lateral flow tests involve rubbing a soft swab around your tonsils and the inside of your nose. Once you've completed the test, you need to report the result online, by calling 119 between 7am and 11pm, or by using the NHS 119 British Sign Language service between 7am and 11pm.
If you need help to do the lateral flow test itself, the government has published a series of guides with instructions on how to do the test and report the results. The instructions are available as a step-by-step guide, in easy read, and in large print: click here to download the guides.
If you have any feedback on getting, using, or reporting the result of any kind of COVID-19 test, please click the pink 'Talk to us' button below to share your views.