When it comes to buying sunscreen, there's a lot to know. For starters, should you be using physical or chemical formulas? SPF 30, or 50? And what does broad-spectrum mean? But after you've done your research, found your preferred ingredients, and have determined which brand, composition, and SPF level of sunscreen is your perfect fit, all that's left to do is apply (and reapply, every two hours) and go have some properly protected fun in the sun, right? Actually, no. While there are a slew of sunscreen application mistakes to be made, one of them is not knowing that sunscreen expires.
Questions? Us, too. Ahead, we enlisted the expertise of two board-certified dermatologists to help us unpack how, why, and when sunscreen expires, plus how to extend the life of your favorite formula.
Meet the Expert
- Dr. Shari Marchbein is a board-certified dermatologist at Downtown Dermatology in New York City. She specializes in acne, esthetics, and laser surgery.
- Dr. Joshua Zeichner is a board-certified dermatologist, as well as the director of cosmetic and clinical research in dermatology at Mt. Sinai Hospital in New York City.
How Long Does Sunscreen Last?
If you're get almost to the bottom of your sunscreen at the end of the summer and keep it in your beach bag for the next time the weather warms up, you're likely guilty of a serious sunscreen sin. According to Dr. Marchbein, this practice is comparable to eating a snack from last summer.
"Like food, sunscreen can go bad and the ingredients can 'spoil,' leading to a watery consistency," she says. And as the ingredients spoil, the sun protective qualities also become less effective, compromising the integrity of the product and leaving you at risk for some serious sun damage.
According to Marchbein, generally, "Sunscreens are designed to remain at their original strength for three years," but that also depends on proper storage. "Heat and humidity also accelerate the breakdown of sunscreen, so be sure to keep it at cooler or room temperatures (so storing in your car is not ideal)," she warns.
As long as sunscreens are properly stored, you can technically use them season to season—but Dr. Zeichner says that regardless, it's better to be safe than sorry. "I recommend purchasing new sunscreen every season because you don't want to take any risks when it comes to the sun and your skin," he says.
How to Tell If Your Sunscreen Is Expired
- Check the Expiration Date: It sounds obvious, but the expiration date is a simple way to check how old your sunscreen is. "Sunscreen is considered an over the counter drug and is evaluated [by the FDA] for stability, giving it an expiration date." So, most bottles do have this stamp on the bottle or box. If not, or if it has worn off, the three year rule applies. Just keep in mind, it's three years past production, not necessarily the date of purchase. Of note, the expiration date also assumes that you have followed the storage directions, which means the expiration date isn't accurate if you've been storing your sunscreen in the garage or space that isn't temperature-regulated.
- Check For a Watery Consistency: Even if you're not a sunscreen expert, there are easy ways to tell if your sunscreen is expired. As Dr. Marchbein explained, a watery consistency is often the first sign of a sunscreen gone bad.
- Check the Smell: Your sense of touch, smell, and sight should alert you to whether or not it's a good idea to keep on using your sunscreen, or whether it's past its prime. Just keep in mind that what might smell or feel okay to use to you might not be the same standard a dermatologist would deem safe.
If you can't read the expiration date, are unsure of whether or not the sunscreen has been stored in a temperature-regulated area, or can't tell for certain if the sunscreen is expired based on smell and consistency, toss the sunscreen and buy a new bottle. Protecting your skin is worth it.
How Bad Is It to Use Expired Sunscreen?
If sunscreen is expired, not only may it not feel or smell the same way, but the integrity of its sun-protecting properties may be compromised, which can be downright dangerous.
Dr. Marchbein explains that if this happens, the sunscreen itself becomes less effective, "Which means a significant increase in the potential for sunburns, sun damage/brown spots and risk for skin cancer development." While an expired lotion may not be entirely ineffective, the likelihood is high that if it has started to break down, it won't be providing you the protection you need.
Sunscreen does expire, and you can tell if it's expired by reading the expiration date or and/or spotting a change in consistency or smell. Dermatologists agree that, when stored in a shaded, temperature-regulated room, sunscreen can typically last up to three years. However, taking risks on whether or not your lotion may be expired simply isn't worth it. And while we should all be more mindful or reducing waste and excess, this really isn't the best scenario to take any chances. We know all too well the dangers of the sun on unprotected skin, so if you're doing the right thing by applying sun protection, it's just as important to be confident that the product will do just that—protect you. When in doubt, throw it out. Just like you would with any other over the counter or prescription medication, or even perishable food item.