Most at-home COVID-19 tests should be used by the date on the box unless the FDA lists an extended date for your exact lot number.
You find a box of COVID-19 rapid tests in a drawer. The printed date has passed. Do you toss it, or can it still tell you something useful?
An “expired” test sits in a gray zone. Some brands received shelf-life extensions after extra stability data, and the FDA posts those extensions by manufacturer and lot. If your lot is not on an extension list, treat the kit as no longer reliable.
Are Old Covid Tests Still Good? If The Box Says Expired
Start with two checks: the printed expiration date, then the lot number. If the lot number appears on an FDA extension list, you can use the extended date even when the box shows an older one. If there’s no extension for your lot, assume accuracy can drop and plan for a fresh test or a lab test.
How Expiration Dates Work On Rapid Antigen Tests
At-home COVID-19 tests use antibodies and chemicals that react to viral proteins. Those materials can degrade over time. The expiration date marks the period the maker has data to show the kit performs within its authorized range when stored as directed.
That date is not a guess. Manufacturers run stability studies, then submit the data under their authorization. When longer storage data becomes available, the FDA can allow a longer shelf life. That’s why some brands have extensions while others do not.
How To Check Whether Your Test Got A Shelf-Life Extension
Look for the lot number on the box (often near the hourglass symbol) and on the foil pouch. Write it down exactly. Then check the FDA’s current list of authorized home tests and extensions. The FDA page is searchable and shows whether the expiration date was extended for each product and, in many cases, for specific lots.
Use the official list here: FDA list of at-home OTC COVID-19 diagnostic tests.
If your brand offers its own lot lookup tool, use that too. For iHealth kits, the company provides a lot-based checker that reflects the latest posted dates: iHealth expiration date lookup.
What You’re Matching When You Search The Lists
Match three things, not one:
- Product name: Some makers sell more than one kit type.
- Lot number: This is the batch identifier tied to stability data.
- Printed expiration format: Some extension tables reference the original printed date and the new date.
If the list says your lot is extended, trust the extended date. If you can’t find your lot, don’t assume it was extended “by default.”
What Can Go Wrong With An Old Test
An expired kit can fail in ways that are hard to spot. The cassette might still show a control line, yet sensitivity can slip. That pushes results toward false negatives, which can lead you to stop isolating or skip a follow-up test when you should not.
False positives can happen too, though antigen tests are generally more likely to miss low viral levels than to invent a positive result. Still, any odd-looking strip, smudged window, or weak control line is a reason to throw the kit out.
Signs Your Kit Should Go Straight In The Trash
- Foil pouch is torn, unsealed, or damp.
- Liquid buffer tube is leaking, dried out, or cloudy.
- Test strip area looks warped or the window is foggy.
- Instructions are missing and you can’t retrieve them from the maker.
- Kit was stored in a hot car, freezing garage, or humid bathroom.
Storage Rules That Make Or Break Test Accuracy
Expiration dates assume normal storage. Heat and moisture speed up degradation. Most brands call for room temperature storage, away from direct sun and steam. Keep each kit in its sealed pouch until the moment you use it.
If your tests sat near a heater, in a glove box, or in a shed through summer and winter, treat them as unreliable even if the printed date has not passed. In that case, replacing the kit costs less than a missed infection.
When Using An Old Test Still Makes Sense
Sometimes you have limited options: a late-night exposure, travel the next morning, or a household where someone is high risk and you need a quick signal. In those moments, an old test can still offer a rough data point if you treat it as a screening step, not a final answer.
If you use an older kit, pair it with a plan: repeat testing over the next day or two with a non-expired kit, or get a lab test if symptoms are present. The FDA’s home-test FAQ explains how to think about antigen results and repeat testing when a negative result clashes with symptoms: FDA at-home COVID-19 test FAQs.
Decision Table For Expired And Near-Expired Tests
This table helps you choose the next move based on what you can verify on the box and how the kit was stored.
| What You See | What It Means | What To Do Next |
|---|---|---|
| Printed date is later than today and kit stored indoors | Within labeled shelf life | Use as directed |
| Printed date passed, and your lot appears on FDA extension list | Authorized longer shelf life for that lot | Use before the extended date |
| Printed date passed, lot not listed for extension | Stability data does not back extra time | Replace the kit; use a lab test if symptoms |
| Printed date passed, lot number unreadable | No way to verify extension | Do not rely on it; replace |
| Box date is fine but pouch is open or damaged | Reagents may be compromised | Discard and replace |
| Kit stored in heat, freezing temps, or high humidity | Storage conditions may have shortened shelf life | Discard and replace |
| Control line fails to appear | Invalid test run | Discard that cassette; retest with a new kit |
| Control line is faint or broken | Run quality is questionable | Retest with a fresh kit |
| You have symptoms after a negative result | Single antigen test can miss early infection | Retest in 24–48 hours or get a lab test |
Step-By-Step: Checking Your Lot Number In Two Minutes
- Find the lot number on the outer box. If the box is gone, check the foil pouch.
- Open the FDA at-home test list and search by brand name.
- Open the row for your exact product name and read any “expiration date extended” notes.
- If the FDA provides a PDF table, match your lot number and the printed date to the extended date.
- Write the extended date on the box with a marker, then store the kit in a dry indoor spot.
If you want a plain-language reminder of the same process, some state health agencies also urge people to check the FDA extension list before discarding a kit. Washington State’s guidance spells that out: Washington DOH expired test kit guidance (PDF).
How To Read Results When The Kit Is Old
If an older kit gives a positive result and the control line is solid, treat it seriously. Limit contact with others and confirm with a new test or a lab test, especially if you need documentation for work or travel.
If an older kit gives a negative result, treat that as “not detected on this run,” not “you’re clear.” If symptoms are present or you had a close exposure, repeat testing over the next 1–2 days with a non-expired kit. Antigen tests work best when viral levels are higher, which is why timing matters.
Timing Tips That Reduce False Negatives
- Test when symptoms start, then test again the next day if the first result is negative.
- If you tested right after exposure, plan another test later; early testing can miss infection.
- Swab as directed. Rushing the swab step is a common reason for weak detection.
Second Table: What To Do After Each Result
Use this as a quick playbook once you have a result in hand.
| Your Result | What It Likely Tells You | Next Move |
|---|---|---|
| Positive, control line clear | Virus detected on this run | Isolate, notify close contacts, confirm with a fresh test or lab test if needed |
| Negative, no symptoms, no known exposure | No detection at that moment | Stay alert for symptoms; retest if you develop them |
| Negative, symptoms present | Possible early infection or low viral level | Retest in 24–48 hours with a non-expired kit or get a lab test |
| Negative, close exposure in last 1–2 days | May be too soon for detection | Retest later; limit contact with high-risk people until you have repeat results |
| Invalid, no control line | Test did not run correctly | Discard that cassette and retest with a new one |
| Positive on an expired kit, negative on a fresh kit | Conflicting results | Get a lab test if you need certainty; act cautiously until confirmed |
| Faint test line within the read time | Positive result if the instructions say any line counts | Follow the kit’s rules, then confirm if you need documentation |
Disposal And Restocking Without Waste
Expired tests belong in household trash unless local rules say otherwise. Keep them out of reach of kids and pets. If you have multiple expired boxes, check each lot; mixed lots in a drawer are common.
When you restock, store tests indoors in a dry spot and mark the verified date on the front of the box.
A Simple Checklist For Your Next Drawer Cleanout
- Sort tests by brand and lot number.
- Check the FDA extension list for each lot.
- Write the verified date on the box.
- Store the rest in a dry indoor spot, away from heat.
References & Sources
- U.S. Food and Drug Administration (FDA).“At-Home OTC COVID-19 Diagnostic Tests.”Lists authorized home tests and notes when expiration dates were extended, often by product and lot.
- iHealth Labs.“Expiration Date Information.”Provides a lot-number lookup tool to verify the latest posted expiration date for iHealth kits.
- U.S. Food and Drug Administration (FDA).“At-Home COVID-19 Diagnostic Tests: Frequently Asked Questions.”Explains how to time antigen testing and how to act on negative results when symptoms or exposure are present.
- Washington State Department of Health.“COVID-19 Expired Test Kit Guidance” (PDF).Advises checking FDA extension lists before discarding a test that shows an expired printed date.