- Check your sunscreen for an expiration date to see if it’s still effective. Even unopened bottles can expire after three years.
- Using expired sunscreen puts you at a higher risk of sunburns and skin damage, so pick up new lotion if you can.
- Heat and sun can also make sunscreen less effective before the expiration date, so toss opened SPF after a year.
When that first unseasonably warm day finally comes and your gut instinct is to get outside, hopefully you second instinct is to reach for the sunscreen. Fair warning: You’ll probably want to skip slathering on last year’s goop. Yep, sunscreen doesn’t last that long — and using it past the expiration date can put your skin at risk.
“You should not use expired sunscreen because it becomes less effective,” says Raman Madan, M.D., a board-certified dermatologist at Huntington Hospital. “This leads to less protection, which means more sunburns, increased risk of skin cancer, and increase in sun damage.”
That’s not the only thing you need to worry about. That old bottle you’ve opened dozens of times before may also harbor more bacteria, which can lead to skin breakouts, Dr. Madan says.
Luckily, there’s an easy way to tell if your lotion is no good. “Sunscreen is considered by the FDA in the same way that an over-the-counter medication is, so it falls under the same requirements for labeling with expiration dates,” says Nicholas J. Golda, M.D., a board-certified dermatologist with the University of Missouri School of Medicine. That means each bottle must have an expiration date, unless lab testing has shown it works as labeled for at least three years.
Changes in color and consistency can also indicate it’s time to go, but a good rule of thumb is to toss out any opened SPF a year or older, says Birnur Aral, Ph.D., Director of the Health, Beauty & Environmental Sciences Lab at the Good Housekeeping Institute.
“Chemical sunscreens work on the principle of absorbing and dissipating UV rays and they can chemically change in that process,” Dr. Aral says. Exposure to sunlight and heat — like when you leave a bottle in your beach bag, on your pool towel, or simply in a hot car — alters the formula on a molecular level. “If you use it, there might be some efficacy, but the SPF might not be as high,” she says.
It’s the same idea behind why you should reapply sunscreen every two hours. After a while, chemical sunscreen loses some of its effectiveness. Mineral sunscreens that use titanium dioxide and zinc oxide act as physical barriers, so they may remain more stable, but the real problem isn’t if your sunscreen has expired — it’s whether you’re actually using enough.
“If a bottle of sunscreen is lasting you and your family longer than its known effective life, it makes me concerned that you may not be applying the sunscreen properly,” Dr. Golda says. The American Academy of Dermatology recommends adults apply about 1 ounce of a broad-spectrum, water-resistant sunscreen at least SPF 30 or higher every 2 hours they’re outdoors. That means a 5- or 6-ounce bottle could last just one day at the beach.
FYI: 1 ounce of sunscreen is enough to fill a shot glass.
This summer, be kind to your skin by seeking out shade, wearing protective clothing, and applying SPF you know will work as intended. Restock your sunscreen supply now with these formulas that got the thumbs-up in our most recent Good Housekeeping Institute tests: