Using At-Home Tests

That means your test didn't work. Note: The letter "C" on a test always stands for "control," not "COVID."

The control is a built-in part of the test to let you know whether the test worked or not. If you don't see a line next to the word "control" or the letter C, throw the test out and take another test.

That means you tested positive for COVID. The letter "T" on a COVID test stands for "test." The letters "Ag" stand for "antigen," which is a kind of protein that the test is looking for.

All of these images show positive tests. If you see any line next to the word "sample" or the letters "T," "Ag," or CoV19," that means the test is positive - even if the line is very light.

Important note! If a line did not show up next to the word "control," the letter "C," or the letters "Ctrl," that means the test didn't work! If that happens, throw the test out and take another test.

Don't forget to report your test result at MakeMyTestCount.org.

This video by a dad and ear, nose, and throat doctor can show you how to swab your kiddo.

The instructions for all at-home tests in the US are available on the Authorized At-Home OTC COVID-19 Diagnostic Tests and Expiration Dates page of the FDA's website.

Find your test in the list and click on the brand name. That will bring up the instructions for your test in Adobe Acrobat. You can use the "zoom in" function to enlarge the instructions.

If it's been kept dry and at room temperature, it'll probably still work, especially if it expired only recently. In fact, it may not be expired at all.The expiration dates of most at-home COVID-only tests have been extended by the FDA.

To find out whether your COVID test's expiration date has been changed:

If you live in California, your state department of public health has decided that you can use your test no matter what the date on the box says, as long as the control line on the test appears when it’s supposed to.

If you don't live in California

1. Go to the FDA's website and look for the brand of test you have. If you see "Extended Expiration Date" in the Expiration Date column (for example, as shown here in the red circle), then the FDA has changed the expiration dates for that brand.

Screenshot of Screenshot of FDA page "At-Home OTC Diagnostic Tests," downloaded Sept. 1, 2023. Test brand names have been hidden.

2. Then, go to the Expiration Date column for your brand of test on the FDA site and click on the link there. That will bring up a page with the old expiration dates (blue arrow) and the new expiration dates (yellow arrow).

Screenshot of FDA pages showing updated expiration dates, downloaded September 15, 2023. Note that pages for some brands of test may not include lot numbers.

3. Next, look for the expiration date on your test's packaging and find that date on the FDA page. The date in the right-hand column is the new expiration date for your test.

Packaging of two sample brands of rapid test. The expiration dates are circled in red.

At-home tests are designed to work at room temperature. So if your test got very hot or very cold, make sure you let it cool down or warm up for at least two hours before using it.

If your test froze, make sure it has completely thawed and come to room temperature before you use it.

If your test was left in very high temperatures (above 86 degrees F / 30 degrees C) for a long time, it may not work.