By now, you know the skin-saving benefits of slathering on the sunscreen when you head outdoors, rain or shine. However, have you ever wondered if you should also be wearing sunscreen indoors? SkinCeuticals specializes in easy-to-wear sunscreens for the face and body that deliver a variety of skin benefits, including broad-spectrum UV protection. That said, if you’re only wearing SkinCeuticals sunscreen when you head out for a day of fun in the sun, you’re missing out on the crucial benefits sunscreen can provide even when you plan to stay indoors. Let’s dig further into the topic and answer some common questions, including:

• Should I wear sunscreen indoors?

• How long does sunscreen last on skin indoors?

• Do you have to reapply sunscreen if you are indoors?

• What SkinCeuticals products are best for wearing sunscreen indoors?

Why you should wear sunscreen indoors

Yes, wearing sunscreen indoors can be a good idea, depending on your circumstance. “If you plan to spend the day inside and are near windows, wearing sunscreen can help protect your skin against UVA rays, which can penetrate glass windows and contribute to premature aging and skin cancer.” says board-certified dermatologist and LovelySkin CEO Dr. Joel Schlessinger. On the other hand, sunburn-causing UVB rays are blocked at nearly 100% by standard window glass. Both UVA and UVB rays cause damage to skin cells that can lead to skin cancer.

How long does sunscreen last on skin indoors?

Most sunscreens are effective for about two hours after application, whether or not you’re out in the sun. “After about two hours, the oil on your skin starts to break down the sunscreen that you’ve applied,” Dr. Schlessinger says. “Even if you haven’t been outside or gotten wet or sweaty, your sunscreen is no longer fully protective after that time has passed.”

Do you have to reapply sunscreen if you are indoors?

If you’re indoors near windows, it’s a good idea to reapply your sunscreen every two hours. “This will make sure you’re effectively protecting your skin against UVB rays that penetrate glass and could potentially damage your skin while indoors,” Dr. Schlessinger says. “The good news is by doing so, you’ll also be protected for any impromptu trips outside you may take as well. Sun damage is cumulative, so the exposure from short trips—from your house to your car and your car to your office, for example—can add up over time.”

Wearing sunscreen indoors: The best SkinCeuticals picks

SkinCeuticals Physical Fusion UV Defense Sunscreen

When it comes to wearing sunscreen indoors, this is one of our favorite formulas to wear all year round. It has a light tint that enhances your natural skin tone and helps enhance your skin’s radiance as well. The texture is lightweight and quick-absorbing, and it protects with a blend of mineral blockers (titanium dioxide and zinc oxide) without leaving a white cast behind.

SkinCeuticals Daily Brightening UV Defense Sunscreen SPF 30

This facial sunscreen is a fantastic choice for indoor wear because it doubles as a hydrating, brightening moisturizer. Glycerin helps draw moisture into your skin, while a blend of 1% tranexamic acid, 0.3% phenylethyl resorcinol and 2% niacinamide work together to help reduce discoloration and leave skin looking brighter. It protects with a blend of chemical blockers (avobenzone, homosalate, octisalate and octocrylene) and feels lightweight and residue-free when layered under makeup.

SkinCeuticals Physical Matte UV Defense Sunscreen

If you’re hesitant about wearing sunscreen indoors because you don’t want your skin to look shiny, give this matte facial sunscreen a try. It contains aerated silica that helps minimize the appearance of large pores and absorbs oil throughout the day for a flattering matte finish. It doubles as a makeup primer, creating a smooth canvas for makeup as well. Most importantly, it provides thorough sun protection for your skin, indoors or outdoors, thanks to a pair of mineral blockers, titanium dioxide and zinc oxide.

Now that you have the scoop about why you should wear sunscreen indoors, you can learn how to choose the best face serum for your skin’s needs.