The most accurate test.
You need only one test. You do not need to repeat the test.
This is the usual test given in a clinic or hospital.
Results may take a couple of days because these tests must be sent to a laboratory.

Antigen test

Positive results are very accurate and reliable. However, in general, antigen tests are less likely to detect the virus than PCR tests, especially when you don't have symptoms.
If the test is positive, you do not need to test again.
To be confident you do not have COVID-19, the CDC and FDA currently recommend two negative antigen tests for people with symptoms or three antigen tests for those without symptoms, performed 48 hours apart. A single PCR test can also be used to confirm an antigen test result. Visit COVID-19 Testing: What You Need to Know for the CDC and FDA antigen testing recommendations.
Answers to Frequently Asked Questions About At-Home COVID-19 Tests.

When to test

Stay home, wear a mask, and get tested right away if you have symptoms, even if you are vaccinated or have had COVID-19 in the past.
If either a molecular or an antigen test result is positive, the virus that causes COVID-19 was found. You do not need to take another test. Visit: If You Are Sick or Test Positive.
If you get a molecular test (e.g., PCR) and the result is negative, the virus that causes COVID-19 was not found and you do not need to take another test.
If you use an antigen test and the result is negative, the CDC and FDA recommend taking a second test. You can:
- Get a PCR test as soon as you can.
OR
- Take another antigen test 48 hours after the first negative antigen test to verify your result.
For more details on repeat testing, refer to the FDA safety communication At-Home COVID-19 Antigen Tests-Take Steps to Reduce Your Risk of False Negative.
Talk to your health care provider if you have questions about what test to use and when to test.

close contact day 0; wear a mask for 10 days, get tested day 6, return to normal activities day 11

Start wearing a mask right away and get tested five full days after being close to someone with COVID-19. Count the day of your last close contact as day zero. Day one starts the day after your last close contact, so you would test on day six.
If your test result is negative, continue to wear a mask for 10 full days, even if you are vaccinated or have had COVID-19 in the past. For information on what to do if you have been in close contact with someone with COVID-19, visit Close Contacts or Exposure to COVID-19.
If symptoms start or you feel sick, get tested right away. Follow the testing instructions above for people with symptoms.
If your test result is positive, the virus that causes COVID-19 was found:
- Visit: If You Are Sick or Test Positive.
- Tell people who have been near you that they may have been exposed to COVID-19.
- You do not need to take another test.
If you get a molecular test (e.g., PCR) and the result is negative, the virus that causes COVID-19 was not found and you do not need to take another test.
If you use an antigen test and the result is negative, the CDC and FDA recommend taking more tests. You have two options:
- Get a PCR test as soon as you can.
OR
- Take another antigen test 48 hours after the first negative antigen test. If your second antigen test is negative, take a third test 48 hours later.
For more details on repeat testing, visit At-Home COVID-19 Antigen Tests-Take Steps to Reduce Your Risk of False Negative: FDA Safety Communication.
Talk to your health care provider if you have questions about which test to use and when to test.
Visit Close Contacts or Exposure to COVID-19 for more on how long to wear a mask, and other precautions to take after close contact with someone with COVID-19.

If you had COVID-19 in the last 90 days, you should still get tested if you have new symptoms. You can still get COVID-19 again, even within 90 days of a previous infection.
Take an antigen test instead of a molecular test if you had COVID-19 in the last 90 days. Molecular tests are able to find a recent previous infection, even after a person has recovered and is no longer able to spread the virus to others.
Talk to your clinic if you are not sure about your test results.
If you had a positive COVID-19 test result within the last 30 days and have close contact with a person with COVID-19, you do not need to get tested if you do not have symptoms. If the close contact happens 31 days or more after you tested positive, you should get tested.

Travel can bring you close to people from areas with higher numbers of people with COVID-19 and other diseases that are spread by breathing the same air.

Be prepared to take a COVID-19 test while traveling. Pack self-tests and know how to find treatment.
If you have symptoms, including before, during, or after travel, take a test right away.
If you know you have been around someone who has COVID-19, get tested.
You may want to take a COVID-19 test if you were in a situation where the risk of getting COVID-19 is greater, for example, on a crowded bus without a mask.
Consider taking a COVID-19 test before visiting someone who is older, immunocompromised, or has a medical condition that puts them at higher risk of getting very sick from COVID-19.
Visit CDC: Travelers' Health: COVID-19 for information on travel precautions like masking, testing, and what travelers can do to prevent COVID-19.

Consider testing on the day of an indoor gathering or event, as close to the time of the event as possible, especially if you will be around older adults and people who are immunocompromised or at higher risk of severe disease. Refer to CDC's People with Certain Medical Conditions and COVID-19 Risks and Information for Older Adults for more information on people at higher risk.
Do not attend any gathering if you have symptoms of COVID-19, regardless of the test result.
Following any event, test immediately if you develop symptoms and visit If You Are Sick or Test Positive for recommendations on how long to stay home, masking, and other precautions.
If you had close contact with someone with COVID-19, test five full days after the event (test on day six, counting the day of the event as zero) and refer to Close Contact or Exposure to COVID-19 for recommendations on masking and other precautions after exposure to COVID-19.

To help protect people at higher risk of getting very sick from COVID-19, consider getting tested before spending time with them.
Consider wearing a mask when around people at higher risk, regardless of the CDC COVID-19 hospital admission level (COVID-19 by County).
People at higher risk include:
- Older adults.
- People who are immunocompromised.
- People with certain lung, heart, and other health conditions.
- Pregnant and recently pregnant people.
If you are at higher risk or have an immunocompromising condition, your health care provider may have different testing recommendations for you.
Refer to CDC’s People with Certain Medical Conditions and COVID-19 Risks and Vaccine Information for Older Adults for more information on people at higher risk.