How Long Does Sunscreen Last on Skin? Tips for Correct Application

Sunscreen is a must-have product in your skincare routine. Without it, your skin is susceptible to damaging UV rays that can lead to skin cancer, sunburn, and premature wrinkles. But its effectiveness may wear off over time, so you have to reapply regularly and correctly. Read on to learn everything about how long sunscreen is effective on the skin, how often to reapply it, and myths and facts about sunscreen application.

How long does sunscreen last on the skin?

How long the sunscreen lasts on your skin usually depends on the type of sunscreen you use and the activities you engage in while wearing the sunscreen. Usually, you can rely on your sunscreen for protection for up to two hours, whether or not it has a high sun protection factor (SPF).

Sunscreen works by reflecting or absorbing the harmful ultraviolet rays before they reach your skin's surface. However, due to factors like swimming, sweating, or simply having an active lifestyle that causes friction against the skin while outside, these protective qualities can wear off with time.

Certain sunscreen ingredients protect you from UV rays by absorbing them and decomposing, thus reducing sunscreen's effectiveness at offering adequate protection from UV after a few hours. This makes reapplying sunscreen every two hours important to ensure continued protection against damaging UV rays during prolonged sun exposure. Make sure you choose a sunscreen that is the best for you according to your skin needs.

Factors that influence sunscreen lasting time

There are different factors that can affect sunscreen protective qualities after applying it to the skin. Some of these factors include:

Water and sweat

Physical activities such as exercising with lots of sweating and swimming can wash away your sunscreen. If you rub your skin dry with a towel, then you can also rub away your sunscreen, so you'll have to reapply it after you've finished exercising or swimming. When you're swimming or exercising, use water-resistant sunscreens. These formulas usually contain ingredients that can form a water-repellent barrier on your skin. This type of sunscreen usually stays 40–80 minutes on wet skin.

Intensity of the sun

The sun's intensity is usually strongest during peak hours, typically between 10 a.m. and 4 p.m. This is when the sun's rays hit us most directly, and UV radiation is at its strongest. During these times, sunscreen's effectiveness can wear off faster due to the increased UV exposure. So, if you are out during this time, reapply your sunscreens more often.

How often should you reapply sunscreen?

In general, you should always reapply sunscreen every two hours while you are spending time in direct sunlight for consistent protection. This will keep your skin protected and still allow a bit of UV rays to pass through to help you tan.

The correct way to apply sunscreen

For sunscreen to protect your skin effectively, you have to apply it correctly. So, how do you ensure you're applying sunscreen the right way? Here are a few easy steps to follow.

1. Choose the right SPF

First, you will want to make sure the SPF you're applying is good. It is recommended to use SPF 30 or higher if you will be spending extended time outdoors. SPF 30 usually blocks 97% of the sun's UVB rays. Always make sure the sunscreen is broad-spectrum SPF, which means it protects against both UVA and UVB rays.

2. Apply the right amount

Most people do not use enough sunscreen. Applying less than what you need can potentially leave you at risk. It takes about 1 ounce of sunscreen to properly cover most adult bodies. Once you have applied the sunscreen, ensure you rub it thoroughly and evenly into the skin.

3. Cover all exposed areas

Always make sure you fully cover all areas of exposed skin. This includes often neglected areas like your ears, behind your knees, and your legs and back. For hard‐to‐reach areas such as your back, you can use a spray sunscreen.

4. Apply before going outdoors

It's best to apply your sunscreen before you step outside, at least 15 minutes before stepping out in the sun. This is because sunscreen needs some time to soak in to be the most effective. If you wait until you're outdoors to apply it, you risk being burnt.

5. Reapply regularly

Reapplying sunscreen is just as important as the first application. Be sure to reapply your sunscreen at least every two hours, as well as immediately after breaking a sweat or swimming, since both will reduce the amount of sunscreen on your skin that you applied before.

6. Don't forget lips and scalp

There are some important areas of the body we usually miss, like lips and scalp. A lip balm with SPF 30 will protect your lips from the sun. Be sure to reapply regularly. To protect your scalp, wear a hat. You can also look for mousse sunscreen for the hairline and scalp areas because they are easy to apply.

7. Layer properly

Applying skincare and beauty products in the right order is essential to maximize protection from the sun. It's best to apply sunscreen after cleansing and moisturizing your face. Give the sunscreen a few minutes to sink into your skin before you start putting on any makeup.

8. Check for expiration date

Like all skincare products, sunscreen does come with an expiration date. Over time, the active ingredients that protect you from UV rays can break down and become less effective. Sunscreen typically goes bad in 2–3 years. The FDA recommends to consider sunscreen expired three years after purchase unless the product label says otherwise.

9. Check UV index

The UV index is a number that tells you the sun's intensity on a given day. It helps to understand how strong the UV rays are and how quickly your skin can burn. You can find the UV index for your area through weather apps or websites. The higher the number, the stronger the UV rays and the greater the risk of sunburn, so more frequent sunscreen reapplication is necessary.

Risks and side effects

Not applying and reapplying sunscreen correctly can be dangerous and comes with several risks. If you don't apply sunscreen or reapply sunscreen properly, your skin will not be as protected as it should be, which can lead to sunburn. The sun's rays can also lead to wrinkles and age your skin faster. Even worse, it can increase your risk of skin cancer. Sunscreen helps block these harmful rays, so reapplying regularly is like giving your skin a protective shield throughout the day.

Myths and facts about sunscreen application

There are some misconceptions about sunscreens that you should be aware of before purchasing your next bottle. Here are common myths and facts about sunscreen.

You don't need to reapply sunscreen if it's water-resistant

Unfortunately, this is completely false. No sunscreen product can be 100% waterproof. So, you must always reapply for waterproof sunscreens after water exposure. Also, allow the sunscreen to settle on your skin for at least 15–20 minutes before going in the water.

A higher SPF means you don't need to reapply as often

All sunscreens, regardless of SPF rating, wear off with time because of exposure to sun, sweat, or water. So, it's important to reapply your sunscreen every two hours or more often if you're sweating or swimming. This also applies if you are using waterproof sunscreens.

You don't need sunscreen on cloudy days

So many people assume that no sun protection is necessary on cloudy days. While clouds may reduce the sun's UV rays reaching your skin, they are not enough to block them entirely. Over 90% of UV rays may still pass through clouds. It's best to apply sunscreen, even if it's cloudy.

Using makeup with SPF is just as effective as sunscreen

Sadly not. Using makeup products with SPF is a good way to add more sun protection to your skin. Makeup with SPF often has a lower SPF rating, which is not enough to provide adequate protection from damaging UV rays. So always make sure you apply a broad-spectrum sunscreen before putting on makeup.

Once applied, sunscreen lasts all day

This is one of the most common myths about sunscreen. Many people seem to think that sunscreen can last all day long after just one application. But, in reality, sunscreen usually decomposes while protecting you from the sun and loses its effectiveness after a couple of hours. Apply sunscreen every two hours or after swimming or sweating.

Sunscreens are essential for protecting your skin from harmful UV rays that can cause sunburn, wrinkles, and even skin cancer. But sunscreen doesn't last forever. So, how long is sunscreen effective on your skin? It can last for up to two hours, so reapply sunscreen every two hours and more often if you're sweating or swimming. Also, the type of sunscreen you use, your skin type, and the amount applied can affect how long it lasts. So, always apply sunscreen generously to ensure your skin is properly protected throughout the day.