YouYou may need to research if you had COVID-19 home tests stored during the Omicron crisis. Like food and medications, rapid COVID-19 tests expire—but figuring out when they go bad isn’t always as easy as glancing at the box.
Here’s what to know about the expiration dates on at-home COVID-19 tests.
When does my COVID-19 test expire?
The components of COVID-19 test kits can degrade over time, potentially affecting the diagnostic’s performance and accuracy, according to the U.S. Food and Drug Administration (FDA). It takes some time to determine how long the product will last. For example, to determine if the test is performing well after 2 years, the manufacturer will need data for at least 2 years. Since rapid COVID-19 tests are relatively new products, companies are collecting much of that data in real time—meaning their expiration dates can and do change.
FDA establishes expiration dates in a conservative manner and adjusts accordingly. To start, at-home COVID-19 tests are typically authorized with expiration dates of four to six months after they’re made, the FDA says. However, the FDA has the ability to extend the window when new data becomes available. That dynamic system means the date stamped on your test’s box may not be its current expiration date.
In January, the FDA extended the recommended shelf life of Abbott’s BinaxNOW test kits from 12 to 15 months, based on data from the company. CareStart tests distributed through the federal government’s free testing program can also be used for three months longer than their marked expiration dates, according to COVID.gov.
The California Department of Public Health went a step further in March, saying that, until further notice, consumers can use any at-home test beyond its expiration date as long as the “control” line shows up normally. Your test kit should contain information about the control line. Officials from Washington State’s health department have also acknowledged that using technically expired but functional tests may be necessary in some cases.
To get the latest information about your tests, check the FDA’s website for updates about antigen tests and molecular tests. A lot number stamped on the packaging may allow you to calculate the expiration date.
What if a test has already expired but I can still use it?
If you’re used to ignoring food expiration dates, you may be inclined to do the same with COVID-19 tests. But—even though some people interpret the dates more liberally—the FDA says not to use expired kits. Dr. Ulysses Wu, system director of infectious diseases at Connecticut’s Hartford HealthCare, agrees it’s best to be cautious, because you may not get accurate results if you use an expired test. “You’re more likely to have false negatives rather than false positives, but that false negative could give a false sense of security when you actually are positive for COVID,” he says.
Since diagnostic expiration dates are a “moving target,” it’s possible that your test actually lasts longer than the box suggests. But, Wu says, “I would just follow [the latest] expiration date and if you really have a concern or you don’t want to throw it away, you can always call the company.”
How do I keep my COVID home tests safe?
Time isn’t the only thing that can affect the quality of a COVID-19 test. Wu states that extreme temperature and moisture can affect the accuracy of COVID-19 tests. To keep medical supplies stable, Wu recommends that they be kept in cool and dark places, such as a cabinet in the kitchen. Wu says, despite its name, a bathroom medicine cabinet should not be used to store diagnostics or drugs.
It is important to stay away from extreme cold. Some people worried that liquid reagents that are used to diagnose the disease might freeze when the U.S. government started giving away free home test kits last winter. While the FDA says that’s not something to be too worried about, tests are meant to be used in environments kept between 59°F and 86°F. You should let your specimen warm up for several hours after it has been in transit.
Wu warns against keeping large quantities of test kits on hand, even though this may seem appealing after the recent supply chain issues. It’s good to have a few around in case someone in your house is exposed to the virus or develops symptoms, but there’s no need to buy a lifetime supply at once, he says—both because they may expire before you can use them, and because it makes it harder for others to get the supplies they need.
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