How Often to Reapply Sunscreen

If you’re wearing sunscreen every day, then you’re already following the number-one rule for sun protection. But there’s another rule that’s just as important—proper reapplication. If you’re not reapplying frequently enough, you’re probably much less protected than you think. And yes, that’s true even if you wear the highest level of SPF available.

Reapplying sunscreen is essential to keep your skin protected. Without proper reapplication, you’re at risk of painful sunburns, skin damage, early aging, and a heightened risk of skin cancer. However, if you haven’t been reapplying correctly so far, don’t worry, you will be soon.

So, how often should you reapply sunscreen? We’ll answer that and more in this article that covers everything you need to know about reapplication, so you can rest assured that you’re taking the right steps to guard your skin against the sun.



How often to reapply sunscreen

Figuring out how often to reapply sunscreen might seem like it should just be simple math based on your SPF, but that couldn’t be further from the truth. While it’s a common misconception, wearing a higher level of SPF doesn’t buy you extra time between sunscreen applications. The level of SPF corresponds to the extent of UVB protection you’re getting from your sunscreen.


Reapply sunscreen every two hours


So, how often should you reapply sunscreen? In general, you should reapply sunscreen every two hours for consistent protection. However, there is an exception to the rule—if you’re sweating or swimming you need to apply more often. To make sure you’re protected even when you’re active, you should reapply sunscreen at least every 80 minutes.


What SPF strength should I use?

As you know, sunscreen is available in several SPF levels, primarily: SPF 15, 30, 50, and 100. One thing we should clear up right away is that SPF level does not correspond to the percentage of protection you’re receiving from that sunscreen. Meaning, SPF 100 doesn’t mean you’re 100% protected and don’t need to reapply throughout the day.


SPF stands for sun protection factor, which measures the level of defense against UVB rays (which cause skin cancer and sunburn). Based on your chosen SPF level, that translates to:

  • Blocking 93% of UVB rays with SPF 15
  • Blocking 97% of UVB rays with SPF 30
  • Blocking 98% of UVB rays with SPF 50
  • Blocking 99% of UVB rays with SPF 100

Because there is only a slight increase in UVB protection once you’re using anything over SPF 15, SPF 30 or 50 are considered the gold standard. Usually, SPF 100 isn’t recommended since it can provide a false sense of security. 

Even if you’re wearing SPF 100, you should be following the golden rule of reapplication—every two hours.


Man applying sunscreen to woman


How much sunscreen do I need?

Now that you know reapplication is the key to consistent sun protection throughout your day, you might be worried that you’re going to go through sunscreen at an alarming (and expensive rate). Of course you will be using more sunscreen than in the past because you’re reapplying properly, several times per day. However, just because you are reapplying more often, doesn’t necessarily mean that you also need to slather on an overabundance of sunscreen.

So what’s the key to using the right amount of sunscreen?

  • Apply sunscreen to your entire face and body
  • Pay special attention to especially sensitive areas like your undereyes, tops of your ears, back of your neck, etc.
  • Rub it in completely—whether that be by hand or our brush-on applicator


One thing to note about Colorescience’s line of UV protectors that can ease your mind about applying too much sunscreen is that, once applied, the formula blends seamlessly with your skin, no matter your skin tone.


How long should I wait before going outside?

The amount of time you should wait before going outside after putting on sunscreen depends on the type of sunscreen you’re using: chemical or physical. Generally, only chemical sunscreen requires you to wait because the sunscreen needs to settle into the skin in order to protect you by absorbing UV rays. For your first sunscreen application of the day when using chemical sunscreen, you typically want to put it on about 15 to 20 minutes before you head outside.


lady applying sunscreen to face


However, if you’re using physical sunscreen, also known as mineral sunscreen, you don’t need to worry about waiting to go outside. This is because physical sunscreen rests on the top of your skin, reflecting away UV rays to protect you. All in all, you don’t need to wait for mineral sunscreen to absorb, so you can put it on on your way out the door if you forget to do it during your morning skincare routine.

It’s worthwhile to also note that since mineral sunscreen doesn’t absorb into the skin, it’s also a safer sunscreen solution. This is because when chemical sunscreen absorbs into the top layers of your skin, it also exposes you to the risk of it potentially entering your bloodstream. Not only that, but it can cause irritation because you’re introducing chemicals to your skin.


For these reasons, mineral sunscreen should be your go-to for sun protection. Shop our Total Protection™ sunscreen collection for a mineral sunscreen that you can take with you on the go.


How long does sunscreen last on skin?

The reason you need to reapply fairly frequently is because sunscreen wears off, becoming ineffective. This happens at a much faster rate if you’ve been sweating or submerged in water. So, how long does sunblock* last on skin? Usually, you can rely on your sunscreen for protection for up to two hours. However, your sunscreen will only last about 40 to 80 minutes with water (or sweat) exposure.


Lady applying sunscreen to leg
Why is there such a big time discrepancy? That’s because sunscreens vary in their water resistance levels:

  • Water resistant sunscreen can provide protection on wet skin for up to 40 minutes
  • Very water resistant sunscreen can provide protection on wet skin for up to 80 minutes
These water resistance levels are determined by criteria set by the FDA.

As far as when sunscreen expires, the FDA recommends that sunscreen should be considered expired after three years, unless the label says otherwise. 

What happens if I don’t reapply sunscreen?

Sometimes we forget to reapply sunscreen, it’s understandable, it’s easy to get caught up in what you’re doing and lose track of time. However, making a habit of forgoing sunscreen reapplication can have painful and even dangerous consequences.

Let’s say you’re up and about ten hours of your day, since sunscreen offers about two hours of protection, that leaves eight hours of exposure without SPF coverage. Or say you go surfing for four hours, that’s nearly three hours of sun exposure out on the water. All that time that your skin’s not protected, you’re susceptible to sun damage.

woman with back sunburn
While there are a range of factors that impact how quickly you get a sunburn, especially the intensity of the UV rays at the time, you can burn in as little as just a few minutes. When your skin gets burned—even if you don’t see visible redness—it causes sun damage. While having this happen one time probably won’t have a notable, long-lasting impact, sun damage does compound with continued, unprotected exposure.

What does that mean for you? It means that over time, your skin can start showing signs of this damage like dryness, discoloration, and signs of aging such as wrinkles. Your biggest risk if you’re not reapplying, of course, is developing skin cancer. According to the Skin Cancer Foundation, correctly wearing a sunscreen of at least SPF 15 on a daily basis can “reduce your risk of developing squamous cell carcinoma (SCC) by about 40% and lower your melanoma risk by 50%.” If you ask us, that’s plenty of motivation to be diligent about reapplication.

Key takeaways for how often to reapply sunscreen

Reapplying sunscreen is critical to protecting your skin, keeping it healthy and youthful looking. Here’s what you need to remember about reapplying sunscreen:

  • How often should you reapply sunscreen? Reapply sunscreen every two hours during regular daily activity.
  • How often should you reapply sunblock* if you get wet? Reapply more frequently—Colorescience water-resistant sunscreens should be reapplied every 80 minutes—when sweating or swimming.
  • How often does sunblock* last on skin? Generally speaking, sunblock* lasts on skin for up to two hours.
  • Do you need to reapply even if you’re using a high SPF? Even if you’re wearing SPF 100, you need to follow these reapplication recommendations.
  • How much sunscreen do you need to use? When reapplying, make sure that you achieve thorough coverage.
  • What is a safe sunscreen to reapply on a daily basis? Colorescience mineral sunscreen is chemical-free, provides UVA/UBA protection, guards against environmental factors like radiation and blue light, and comes in a variety of application options so you can take it on-the-go all the time.

Now you’re ready to enjoy endless hours in the sun with the peace of mind that you’re reapplying sunscreen correctly and providing your skin with the protection it needs to remain healthy and radiant.
*Sunblock is not a term approved by the FDA. Colorescience refers to our products as sun protection.