Can You Use an Expired COVID Test? Expert Doctors Answer
At-home COVID tests have a specific shelf-life. Experts explain how to tell when an expired COVID test is useless, and when it could still be in good working order.
You’re feeling rundown and find a COVID test stashed in the medicine cabinet—but you think it might be from one of those early batches that came in the mail for free, and now it’s expired. Sigh…so now do you need to figure out the quickest way to get your hands on a new one?
The US Department of Agriculture (USDA) tells us that expiration dates indicate when the quality of a consumer product, like food, vitamins, or medication, starts to decline. The USDA also points out that many items stay relatively safe or effective for a window of time past that expiration date. When it comes to an expired COVID test…is it worth trying to use?
Probably not, answers The Ohio State University Wexner Medical Center assistant professor of pharmacy Jeffrey Pilz, PharmD, MPA, MS—however, Dr. Pilz says, there’s also a way to double-check if your COVID test is truly expired, regardless of what the expiration date reads.
Here’s when an expired COVID test isn’t helpful
Says Dr. Pilz: “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 ingredients in the test may break down over time—so, he explains, “if using an expired test kit, it may still show a positive or negative result, but there could be a large risk that the result is false.”
This is a problem because experts say the most dominant COVID-19 strain this season, E.G. 5 (Eris), tends to cause mild symptoms—but is extremely transmissible (which means contagious). So even if you don’t feel sick, relying on a false negative result from an expired COVID test could risk spreading the COVID virus to someone more vulnerable.
In addition, some older COVID kits probably don’t test for the more recent strains, explains Sorana Segal-Maurer, MD, director of Infectious Disease at NewYork-Presbyterian Queens. “The Food and Drug Administration (FDA) works with test-producing companies and follows the tracking of new strains to evaluate ongoing suitability of the currently approved tests.”
How to tell when COVID tests expire
Depending on the brand, a home COVID test’s shelf-life can range from four months to two years. You can find the shelf life by brand on the FDA’s website—and an individual test’s expiration date is listed on the box label.
Even so, that expired test lying around may still be usable after all, as the FDA recently issued “extended expiration” dates for about half of the COVID test kits it had previously approved. Dr. Pilz explains: “Stability testing continues at the manufacturer even after FDA approval, allowing the FDA to extend expiration dating when there is sufficient evidence to ensure that the test still provides a valid result.” On the FDA website, you can find these extensions based on brand and a product’s lot number (also listed on the box).
This is also important to know because as of September 25, 2023, all US households can order four free COVID test kits from the government—and a notice on the order site says that the box(es) you receive may appear expired. “The test box might already have been printed or shipped before the extended expiration was approved, so the date on the test itself will still appear within that short shelf life,” Dr. Pilz says.
Can a COVID tests go “off” before its expiration date?
Dr. Segal-Maurer says the PCR test is still the gold standard, as it can detect the virus even with limited symptoms. “Though antigen (at-home) tests are very accurate, they rely on the presence of symptoms,” she says, and they’re generally less likely to pick up on early infections. This is why taking a second home COVID test after 48 hours is often recommended—especially if you tested negative the first time. ALSO READ: New Study: If You Test for COVID on This Day of Symptoms, You May Be Testing Too Early
This at-home COVID test reliability depends on three main factors:
- that the test is within its shelf-life (or extended expiration)
- that you follow instructions
- and that the test had been stored properly in your home. Says Dr. Pilz: “Similar to medications, keep any extra test kits in a dry location, secured away from pets or children, ideally with a consistent room temperature. Areas like bathrooms often have high humidity, so that medicine cabinet will not always be the best choice!”
Keep in mind, he adds: “Any sort of manipulation, chemical exposure, or not following test directions can lead to incorrect results.”
- 13 Things You Should Never Eat Past the Expiration Date
Jeffrey Pilz, PharmD, an assistant professor of pharmacy at The Ohio State University Wexner Medical Center
Sorana Segal-Maurer, MD, Director of Infectious Disease at NewYork-Presbyterian Queens
US Department of Agriculture: "Before You Toss Food, Wait. Check It Out!"
Centers for Disease Control and Prevention: "Update on SARS CoV-2 Variant BA.2.86"
Centers for Disease Control and Prevention: "Get four free at-home COVID-19 tests this fall on COVIDTests.gov"
Food and Drug Administration: "At-Home COVID-19 Antigen Tests-Take Steps to Reduce Your Risk of False Negative Results: FDA Safety Communication"