Your ‘expired’ COVID-19 home tests might not be expired yet

As of Sept. 26, 2024, COVID-19 home testing kits are available again free of charge, provided by the government through the United States Postal Service. Each household can get up to four tests (see more at covidtests.gov).

You may notice some of these tests are past the printed expiration date, but some resources say they're still OK to use. A U.S. Food and Drug Administration (FDA) webpage (fda.gov/covidtestdates) lists your home COVID-19 test's extended expiration date, if applicable.

So, why have expiration dates on these tests, and how can they be extended like this?

What expiration dates mean on COVID-19 tests

Expiration dates on COVID-19 test kits are the end of their “shelf life.” Similar to expiration dates on groceries and medicines, an expiration date on a home test kit represents the latest date the manufacturer can guarantee that the result will be as accurate and reliable as when first produced.

When developing their tests, each manufacturer performs stability studies to determine how long the kit can be used before there’s too great a risk of invalid or false results. Some of the components in the tests may break down over time, so, unfortunately, they can’t be used forever.

Why COVID-19 tests are able to have extended expiration dates

These COVID-19 home tests were created when rapid approval and availability was needed at the height of the pandemic. In these situations, the FDA may grant approval for a test with limited stability testing performed at that time. The manufacturer might have only completed a few months’ worth of studies, and thus had to send out lots of tests marked with expiration dates that seem to give them a short shelf life.

However, stability testing continues at the manufacturer, allowing the FDA to extend expiration dating when there is sufficient evidence to ensure that the test still provides a valid result. The test box might already have been printed or shipped before the extended expiration was approved, so the date on the test will still appear within that short shelf life.

How to know if your COVID-19 test has an extended expiration date

If the printed date on your COVID-19 home test is in the past, check the FDA website to determine whether the test received an extended expiration date and to see what the new expiration date is.

If you don’t see your kit’s brand and lot number on the list of those with extended expiration dates, you should treat the kit as expired and use a new, in-date kit instead.