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Is your old sunscreen past its prime?

A person’s hand squeezes sunscreen from a tube into the palm of their other hand.

May 1, 2025—Warmer weather is here! Time to grab your shades, dig up that sunscreen and head outside. But before you roll out, ask yourself one question: Is my leftover sunscreen still good to go?

Sunscreen, like many other products, has an expiration date. These handy rules of thumb can help you know when it's time to throw out your old sunscreen and buy new. Plus, discover the best ways to apply sunscreen to reduce waste and maximize your skin's protection.

Why are expiration dates important?

Sunscreen has active ingredients that block and absorb the sun's UV rays. It's important to keep track of your sunscreen's expiration date because these ingredients can become less effective over time. Keeping your sunscreen past its prime also increases the possibility that mold or bacteria may develop in the container.

For these reasons, using expired sunscreen can lead to:

Sunburn.
Skin infections.
Allergic reactions.
Irritated skin.
Early skin aging.
Skin cancer.

How do I know if my sunscreen is expired?

The U.S. Food and Drug Administration requires sunscreen to have an expiration date on the container—unless tests show it can hold its original strength for three years. If you can't find the expiration date, write the date you bought the sunscreen on the container. Make sure to throw it away three years after that date.

Keeping track of all sunscreen expiration dates in one place can help you stay organized and help keep your skin healthy and protected.

Other signs your sunscreen has lost its shine

Sometimes your sunscreen hasn't expired, but it may still be spoiled. This could happen when it's left in hot spaces—like a car or the sun—which can cause the active ingredients to become less effective.

According to the American Academy of Dermatology (AAD), these key signs mean it's time to toss your old sunscreen:

It smells "different" than usual.
The color has changed.
It's dry and flaky.
Its odor is foul.
The ingredients have separated (like into liquid and solid layers).

Savvy ways to apply your sunscreen

The best way to avoid wasting sunscreen is to apply it regularly—and correctly. If you wear sunscreen every day as dermatologists recommend, the AAD notes that you'll likely use up a bottle fairly fast.

When applying your sunscreen:

You'll need at least 1 ounce—about a shot glass full—to cover your body.
Use a nickel-sized drop on your face.
Remember the skin of your eyelids, hairline and ears.
Reapply the sunscreen at least every two hours—or more often if you're swimming or sweating.

When your bottle is gone (or expired) and you need to replace it, this sunscreen shopping guide can help you pick the best type for every situation.

Sources

American Academy of Dermatology. "Sunscreen FAQs." https://www.aad.org/media/stats-sunscreen.
American Academy of Dermatology. "When to Toss Your Makeup and Sunscreen." https://www.aad.org/public/everyday-care/skin-care-secrets/prevent-skin-problems/replace-makeup-sunscreen.
Skin Cancer Foundation. "3 Reasons Why Your Sunscreen Isn't Working." https://www.skincancer.org/blog/3-reasons-why-your-sunscreen-isnt-working.
U.S. Food and Drug Administration. "FDA Insight: A 'Topical' Discussion on Sunscreen." https://www.fda.gov/news-events/fda-insight/fda-insight-topical-discussion-sunscreen.