An illustration of a sunscreen container melting.
Illustration: Ben Bours

The unofficial start of summer, Memorial Day, isn’t too far off. And it’s around this time that many people start taking stock of their sunscreen supply. Do you need to buy a new bottle, or will what’s left in last year’s tube do the job? 

It depends. Sunscreen remains effective for three years, but it does expire, so check the date on the container and don’t use it if the date has passed. 

However, not all containers of sunscreen carry a date. As long as the sunscreen has been formulated to stay stable for three years, the Food and Drug Administration doesn’t require one.

More On Sun Protection

If your sunscreen doesn’t have an expiration date and you can’t remember when you bought it, you shouldn’t take a chance that it will still protect you. Buy a new bottle and use a permanent marker to write the date you purchased it on the container.

But even if your sunscreen expiration date is in the future, whether it is still really effective also depends on how you’ve stored it.

“Heat and humidity can accelerate the breakdown of sunscreen,” says Susan Booth, who oversees sunscreen testing at Consumer Reports. “If the bottle or can is in your car or bathroom, the temperature fluctuations may have affected the product. But if it’s been kept at room temperature, you’re good to go.” Properly stored, a sunscreen that has an expiration date of six months away should work as well as one that has an expiration date of three years away. 

This is true even if you have only half a bottle or so left over. “Opening a sunscreen, using some, and recapping it will not cause the sunscreen to go bad any faster,” Booth says. “We have retested sunscreen samples from the previous year’s testing after storing them in our lab and found no differences in performance.”

If the contents of the sunscreen have separated—“spoiled” sunscreen will be watery—or if it has changed color or has a funny smell, toss it even if it hasn’t expired.

If you need a new sunscreen, consider one of these top-rated products from Consumer Reports’ tests.  

Unlock Sunscreen Ratings
Quick Take
Unlock Sunscreen Ratings
Unlock Sunscreen Ratings
Unlock Sunscreen Ratings

Sunscreen Protection

Do sunscreens really protect as much as they claim? On the “Consumer 101” TV show, Consumer Reports expert Sue Booth breaks down what you need to know to keep you safe from the sun’s harmful rays.