Most People Apply Sunscreen Wrong. Are YOU Doing It Right?

I won’t lecture you about using sunscreen every day. I know you know it’s the best way to prevent wrinkles, dark spots, and even cancer and are using it every day. BUT, are you applying sunscreen the right way? Sunscreen ain’t like other skincare products. If you don’t apply enough product, get the application order wrong, or mess up another little detail, you risk compromising the sun protection you’re getting and exposing your skin to all kinds of damage. So how do you apply sunscreen the right way? Here are all your questions about sunscreen application answered:

1. What’s The Right SPF Number To Use?

In the past, the recommendation was to use SPF15 in winter and SPF 30 in the summer. That’s not going to cut it anymore. I recommend you use a SPF of at least 30 every day. Why? No sunscreen protects from ALL UV rays. SPF15 only blocks 93% of UV rays. SPF 30, on the other hand, blocks 97%! A big jump! That makes SPF 30 ideal for daily use. It’s not so thick, it’s unpleasant to use and protects you from UV rays.

“The American Academy of Dermatology always recommends an SPF of 30 because it is clinically proven to be a sufficient amount of protection to reduce or minimize the adverse effects of sunlight,” explains NYC dermatologist David Colbert, MD.

If it’s summer or you’re leaving in a torrid climate, upgrade to SPF 50. It protects you from 98% of UV rays. A 1% difference may not seem to make much of a difference, but every little % counts when it comes to sun protection. The stronger UV rays are, the higher the number you should apply.

Dr Joshua Zeichner, MD, the director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City, explains why: “In the real world we do not apply as much sunscreen as we should and we do not reapply. This ultimately means that the SPF value is diluted out. Starting with a higher SPF serves as a safety net to ensure the highest quality of protection for the longest period of time.”

Keep in mind that SPF 100 or higher only protects from 99% of UV rays – and still needs to be reapplied as often as lower SPF numbers to get the level of protection stated on the bottle. Don’t skimp!

2. How Much Sunscreen Should I Apply?

Almost NO ONE applies enough sunscreen. “To achieve the SPF reflected on a bottle of sunscreen, you should use approximately two milligrams of sunscreen per square centimeter of skin,” says NYC dermatologist Dendy Engelman, MD. How much is that in plain English?!

“This is about the equivalent of a shot glass full, or about two tablespoons,” Dr Engelman continues. “For the face alone, a nickel-sized dollop should be applied. And if you’re using a spray, apply until an even sheen appears on the skin.”

FYI, keep in mind thatLeveryone’s face is a slightly different size. If your face is smaller than average, you can get away with applying a little less. Michelle of Lab Muffin, one of my fave beauty science blogs, has done a little experiment, measuring exactly how much sunscreen she should apply. Turns out, she only needs  61% of a teaspoon for her face. You can check out Michelle performing the experiment (and putting tape all over her face) here.

Related: How Much Sunscreen Do You Need To Apply To Get The SPF On The Bottle?

How effective is your sunscreen? Sign up to the newsletter below to receive the “Sunscreen Audit” Worksheet and find out if your sunscreen is really up to the job:

3. What Goes First: Moisturiser Or Sunscreen?

I recommend you always apply moisturiser first. Here’s why:

1. In studies measuring its effectiveness, sunscreen is always the last product applied to the face. Makes sense to use it as they test it to make sure you’re getting the best possible sun protection for your skin.
2. Touching your face after putting on sunscreen can disturb it, remove it, and generally make it less effective. So, if you apply anything on top of sunscreen, especially before the film it creates takes time to settle, you risk removing sunscreen here and there and leaving your skin prone to sun damage.

FYI: the more products you apply in the morning, the higher the chance your sunscreen won’t spread properly. For best results, use only the number of products you absolutely need. My skin is fine with cleansing, Vitamin C, and sunscreen in the morning. I only add a moisturiser in winter. Listen to your skin, always!

Related: In What Order Should You Apply Sunscreen?

4. Can You Mix Sunscreen With Moisturiser?

No! No! No! Please, ladies, don’t do this! I know a lot of sunscreens out there are thick and greasy. Mixing it with moisturiser makes the texture lighter, more pleasant to use, and easy to spread on the skin and save yourself some time in the morning too).

But mixing your sunscreen with moisturiser (or anything else, for that matter), dilutes the SPF. Instead than SPF 30, you may well be applying SPF 11! In other words, when you mix sunscreen with your moisturiser, you won’t be getting adequate sun protection! Don’t take that risk. Layer them on top of each other instead (moisturiser first, remember?).

Related: Why You Should NEVER Mix Your Sunscreen With Moisturiser

5. Can You Layer Chemical & Mineral Sunscreens?

Before I answer this question, here’s a short primer on the difference between chemical and mineral sunscreens:

• Mineral sunscreens: Sunscreens that use mineral filters, i.e. zinc oxide and titanium dioxide. They’re very gentle on the skin and suitable even for sensitive skin and pregnant women. But they tend to have a thick texture and leave a white cast on your skin. To avoid the latter, opt for a tinted formula.
• Chemical sunscreens: FYI, even mineral sunscreens are chemical (everything made of matter, including water, is a chemical). But, when it comes to sunscreen, we call chemical every product that contains every other UV filter – like Avobenzone and Mexoryl. They tend to be lighter on the skin and leave no white residue behind, but can be irritating for sensitive skin.

There’s a common myths that mineral and chemical UV filters work differently. That’s not true. ALL UV filters work by creating a film on the skin that absorbs UV rays and turns them into a less damaging form of energy (heat). Some UV filters also reflect a small amount of UV light away from your skin.

If you want to layer two sunscreens on your face, there’s no reason why you can’t do it. Just be aware that SPF isn’t cumulative. Here’s why: the SPF number tells you how many UV rays your sunscreen can block. For example, SPF 30 blocks 97% of UV rays while SPF 50 blocks 98%. So, if you apply a sunscreen with SPF 30 followed by a sunscreen with SPF 50, the layer on your skin will block 98% of UV rays.

In other words, when you layer sunscreens, you get the sun protection of the highest SPF you applied – in this case SPF 50. Layering isn’t completely useless, though. Most people don’t apply enough and miss spots. If you use two sunscreens, you increase your chances of getting everything covered. Or, you could just spend a bit more time applying that one sunscreen everywhere. Your choice.

Related: Sunscreen Math: Can You Add Up SPF?

6. Should I Pat or Rub Sunscreen On?

I’m Team Pat all the way. If you think I’m crazy, I totally get it. Sunscreen is thick, so it takes a few minutes to pat it in. Rubbing it on makes application much faster. But faster doesn’t always equal more effective. Scientific studies have proven that patting sunscreen on is the right way to do it.

A 2006 study found that “protection by a four star-rated sunscreen (with UVA protection) was optimal when applied as a thin film (40-60% at 2 mg cm(-2)) but less so when rubbed into the skin (37% at 4 mg cm(-2) and no significant protection at 2 mg cm(-2)), possibly due to cream filling crevices, which reduced film thickness.”

Before we go any further, thin film doesn’t mean you can apply less than the recommended amount. It means that, when you apply it properly, sunscreen should form a thin layer on your skin. If you rub the sunscreen in, you could REMOVE it a little here and there, reducing the thickness of the film (and the sun protection it provides) in some areas. If you want to rub it in, do it as gently as possible so as not to compromise this thin film.

Related: Pat Or Rub: What’s The Best Way To Apply Skincare Products?

7. How Long Do I Need To Wait After Applying Sunscreen Before Going Outside?

First off, let’s debunk the myth that mineral sunscreens work straight away, while chemical sunscreens need 20 minutes to get activated. Even dermatologists promote this myth and it is NOT true! All sunscreen work right away – as long as you apply them correctly.

As a rule, you need to apply sunscreen about 20 minutes before going outside. Why? Sunscreens create a film on the skin that protects it from UV rays. Think of sunscreen like paint. It you touch the paint before it’s dry, you’ll remove it.

Sunscreen is the same. Touch your face before it settles and you’ll risk removing the sunscreen in those spots. It takes 15-20 minutes for sunscreen to form a film on your skin. If you can, wait that long before leaving the house to get maximum sun protection.

Related: The Real Reason You Need To Apply Sunscreen 20 Minutes Before Sun Exposure

8. How Long Should I Wait After Sunscreen Before Applying Makeup?

Always wait 20 minutes, give or take, after sunscreen before applying makeup. Yes, I’m serious. I just told you sunscreen needs time to settle and form a film on your skin, remember? You know what happens when you apply foundation straight after sunscreen? You remove it, that’s what.

Let me say it again: anything that touches your face while the film is drying has the potential to remove your sunscreen and compromise its protection. If you really can’t wait that long before putting on makeup, lightly stipple your foundation on. It’s the gentlest way to apply it, minimising the risk of compromising the delicate sunscreen film.

Related: Is Your Foundation Application Messing With Your Sunscreen?

9. How Often Should You Reapply Sunscreen During The Day?

It depends on how much sun exposure you’re getting during the day. Let me explain. UV filters get deactivated by sunlight, can be rubbed off of your skin (for example, when you towel dry) or removed through sweat and natural oils.

But how long does it take for this film to become completely ineffective? That’s the million dollar question. You see, the sun’s rays are stronger in some hours (between 10am-4pm) and weaker in others. In winter, the sun is weaker and doesn’t stay around as longer. Sometimes, the sun is completely covered by clouds (but UVA rays will still get through).

Not to mention, you don’t spend the same time outdoors every day. When the weather’s sunny and hot, you can spend hours playing outside. Other days, you’ll just leave the house to get to work and back. On some days, you may not leave the house at all.

In other words, the amount of UV light your skin is getting depends on different factors. And how often you reapply your sunscreen depends on all these factors.

• If you’re at the beach, spend a lot of time outdoors, sweat or swim, you need to reapply your sunscreen every couple of hours (it’s easier if you keep your makeup simple).
• If you’re getting very little sun exposure, like simply walking to your car and commuting to work, you may not need to reapply at all. Especially in winter.
• If you’re getting moderate sun exposure, reapplying once in the middle of the day may be enough. And when you’re in doubt, reapply it (better be on the safe side).

Related: Do You Really Need To Reapply Sunscreen Every 2 Hours?

10. Should I Use Sunscreen Even If I’m Staying Indoors?

Yes! UV rays are sneaky and can penetrate through windows, so you’re not 100% safe indoors. “UV exposure can occur from ultraviolet that penetrates through glass, which is UVA,” says LA dermatologist Ava Shamban. “UVA is emitted at the same level  all day long whereas UVB, which is blocked by glass, peaks midday.”

But that’s not the only reasons why experts and dermatologists recommend sunscreen even when you don’t plant to go outside of hours. “Completely indoor activities don’t require sunscreen, but many of us discount the sun that we get on a daily basis from just running errands and all the ‘incidental’ sun damage adds up,” explains dermatologist Elizabeth Tanzi. “That’s why we recommend daily sunscreen application, so you are always protected and don’t have to think about it.”

Sunscreens: Best Picks

Wondering what the best sunscreens here? Here are my favourite sunscreen recommendations:

• Drunk Elephant Umbra Tinte Physical Daily Defense SPF 30 ($36.00): A tinted mineral sunscreen that protects you from all UV rays without leaving a white cast behind. Best suitable for dry skin. Available at Boots, Cult Beauty, SpaceNK, and Ulta.
• La Roche Posay Anthelios Clear Skin Dry Touch Face Sunscreen SPF 60 ($19.99): Ideal for oily skin, this lightweight sunscreen provides broad spectrum protection and absorbs excess oil for a matte finish. Available at Boots, Dermstore, La Roche Posay, and Ulta.
• Paula’s Choice Defense Essential Glow Moisturiser SPF30 ($26.40): Suitable for all skin types, this tinted mineral sunscreen provides broad spectrum protection, fights premature wrinkles, and dries to a luminous finish. Available at Cult Beauty, Paula’s Choice, Sephora, Selfridges, and SpaceNK.
• Shiseido Ultimate Sun Protection Lotion Broad Spectrum SPF 50+ WetForce for Sensitive Skin and Children ($42.00): A high SPF, broad spectrum protection formula that’s gentle enough even for children and sensitive skin. It’s water-resistant for up to 80 minutes. Available at Sephora and Ulta.
• Supergoop! Mineral Mattescreen SPF 40 ($38.00): A mineral sunscreen that provides broad-spectrum protection and dries to a silky matte finish. It also minimises the look o pores. It’s best suitable for oily and combination skin. Available at Blue Mercury, Nordstrom, Revolve, and Ulta.
• Ultrasun Ultra Sensitive Very High SPF50+ Extreme Formula (£30.00): This sunscreen uses the new generation of chemical filters to provide broad spectrum protection without the irritation. Suitable for sensitive skin too. Available at Boots, Sephora, and SpacenK.

The Bottom Line

To make the most of your sunscreen, pat it on generously after moisturiser, at least 20 minutes before leaving the house – even when it’s rainy or you’re staying indoors for the day. The more of the tips above you follow, the better protected you are against those pesky UV rays.

About Gio

Hi, I'm Gio. I'm a no-nonsense, tell-it-like-it-is skin coach and writer on a mission to help you achieve your best skin day ever - every day. I bust skincare myths and debunk marketing jargon to help you figure out what's worth the splurge and what's best left on the shelf - using science, not hype. I also offer skincare consultations to help you create the best skincare routine for your unique needs.