Home testing has been a critical tool in humanity’s efforts to stop the spread of COVID-19. You may have bought some at your local pharmacy or ordered them for free through the program the US government launched in January. But they can expire the moment you show symptoms.
The good news is that the Food and Drug Administration, the agency responsible for authorizing COVID tests, is constantly using new data to extend the shelf life of these useful products. This means the ones you have at home can last up to 14 months beyond the expiration date on their packaging. All of this information is on the FDA website, but you will need guidance to navigate it.
Check the expiration date of your COVID test at home
It’s been a couple of days since your friend’s indoor birthday party and now your throat is sore and your joints are starting to ache. It’s time for a COVID test.
If your test expiration date has passed, go to the list of FDA-approved home COVID tests and check the database at the bottom of the page. You can use the search bar by entering the make and model of your test, or you can display all the entries in the list by clicking the dropdown to the right and selecting show all posts. As of this writing, the FDA has authorized only 22 tests in the US, so displaying the full list won’t force you to scroll ad nauseam..
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Next, find your proof. An earlier version of this database only had the test names in the first column, but the FDA has since included some visual aids in the form of thumbnails showing the packaging of each test. This makes it easy to see which entry corresponds to what you have at home, and you can scroll down the list until you find the correct box. When you do, confirm that the make and model of your test match the entry.
In each entry, you’ll find all sorts of useful information for each test, including who can use it, what kind of sample it requires, and how long it takes to get results. The information you will need to know when a COVID test is due is in the last column, all the way to the right, below Date of Expiry. There, you will see the life of the test and if it has been extended. If so, you will see the word (extended) right next to it, and a link to a PDF with a list of all updated expiration dates.
If the shelf life of your test has been extended, you will need to confirm that the extension applies to the specific group of tests (the batch) that your test came from. Open the PDF to find a list with three columns: from left to right, you’ll see lot numbers, original expiration dates, and extended expiration dates. To find the lot number for your test, you will need to look at the chart; You’ll most likely find this six-digit number on the back or side, usually on a label next to the word BATCH.
Go back to the PDF and use your browser’s “find” function to locate the lot number: if you’re using a Mac computer, press Command+Fand if you are a Windows user, press Ctrl+F at the same time. In the pop-up search bar at the top right corner of the browser screen, type your test lot number. Your browser should automatically scroll down to where the number is and highlight it. Note that the original date (middle column) matches the date printed on the box, and then look at the third and last column for the actual expiration date. If that hasn’t happened yet, it’s good to take a sample; hopefully, the test comes back negative.
If your lot number is not listed, you must adhere to the expiration date printed on the box. And if that’s already happened, the FDA says the test may provide inaccurate or invalid results, so you should throw the test away and get a new one.
With the first testing method, manufacturers simply let a batch of tests sit for a period of time (seven, 13, or 19 months) and then see if the tests still work as well as when they first left the factory. . This method is the most reliable way to ensure that the tests work correctly, but it is slow because it requires real time to pass before the manufacturers can test the tests.
[Related: You can, and should, order more free COVID tests from the US government]
But at the height of the COVID-19 pandemic, we couldn’t wait almost two years to make sure the tests met standards, so the manufacturers used accelerated stability tests. This method involves storing a batch of tests for a shorter period of time at a high temperature and then checking to see if they still work accurately. They are tested to ideally work between 59 and 86 degrees Fahrenheit (approximately 15 and 30 degrees Celsius). Extreme temperatures can degrade them more quickly, mimicking the effect of sitting on a shelf for a long time.
This method was helpful from the start because it allowed the FDA to approve the tests and get them into our homes quickly to help us slow the spread. But because accelerated stability tests aren’t as accurate as letting time pass, the agency only gave the tests a shelf life of four to six months that could be updated once manufacturers provided more stability data.
That is what is happening right now, and we may continue to see extended expiration dates for at-home COVID tests as more time passes. For now, however, be sure to check the FDA’s website before you discard your tests, and take precautions to protect others if you need to go into a public space for a new test.
