When you open TikTok or Instagram, it seems like every “Get Ready With Me” video features someone slathering on layer after layer of fancy skincare serums. The pressure to have an extensive skincare routine is real, and sometimes it can feel like you’re supposed to be using every serum and active ingredient under the sun for that elusive “best skin ever.” It’s no surprise, then, that people wonder if they should be layering serums. How many should you be using? What kinds can you mix together? There are even “recipes” online for creating your own bespoke routine by mixing various serums together before applying them. At first, it might seem like a great idea. After all, there are so many high-performance skincare ingredients out there these days, why not add some of them together to give your skin as many benefits as possible?
Thankfully, though, the answer to all this is refreshingly simple. Mixing and layering your serums won’t give you the best results—you should be rotating one at a time instead. Keep scrolling to learn why layering and mixing aren’t the way to go, how to rotate your serums, and which ingredients you should never mix.
First, What Is a Serum?
A serum is a concentrated skincare product with active ingredients. They are typically lightweight and water or lotion based because this allows them to penetrate deeper into the skin where they can create the most change. Where a cleanser, toner, and moisturizer are the building blocks of a solid routine, you reach for a serum to target specific concerns and create tangible change. Be it acne, dehydration, discoloration, or signs of aging—there’s a serum for that.
A serum should always be applied after you’ve cleansed and applied toner, then followed up with moisturizer.
Read what is a serum, and do I really need one?
Should You Layer Serums?
As I said earlier, there are so many amazing active skincare ingredients available that it seems like using more than one would maximize results. But What actually happens when you layer serums on top of one another?
Let’s say you start by applying a niacinamide serum then layer a vitamin C serum on top of that. The first serum is going to penetrate the skin as it’s meant to, but it will probably also leave a little residue behind on the skin’s surface. This means the second serum has a bit of an obstacle and might not be able to penetrate as effectively. The more serums you add, the more diluted they become. To go back to our example, this could mean the vitamin C serum you apply is now half as effective as it’s meant to be.
While it’s tempting to load up on multiple products and ingredients, your skin can only absorb so much. Think of it as a sponge; at some point, a sponge has absorbed all it can and water will just pour over it. This happens with your skin as well. Trust me, by using everything at once, you’ll just end up throwing your money down the drain.
Another concern is that many serums include very active ingredients. When you apply too many strong ingredients to your skin at once, you run the risk of irritation. That will only cause damage and undo all the good you were trying to do with your serums.
If you’re intent on layering, I don’t suggest more than two serums—one with an active ingredient like retinol or exfoliating acids, and one that’s purely a hydrating serum. These tend to play nicely with others and can add a little extra layer of moisture if that’s what you’re looking for.
What About Mixing Serums?
So layering is all good, but what about mixing everything together to create on super-serum? Hate to burst your bubble, but it doesn’t work this way either.
Even if the ingredients in two different serums can technically be combined, you still run into the issue of dilution. Again, you’d be wasting your money by not getting full benefits from the product.
Let me also make this point. Not all serums are equal. Chemically speaking, one formula may be designed to penetrate via a certain mechanism. Another product may not have the same penetration enhancers. You may be making them chemically less efficient, by disrupting their intended processes. Basically, it’s like you’re confusing the serums by mixing them together.
Lastly, I never recommend mixing water-based products with oil or emollient-based products. I know some people like to mix their serums into moisturizer, and I’m not a fan since this can really mess with the efficacy of a serum. It’s best to apply a serum, let it dry down or get tacky for a few seconds, then apply a thin layer of moisturizer on top.
How Can You Get All the Benefits Without Layering Serums?
It’s true that you’ll get the greatest benefit by using a variety of active ingredients, so here’s the best way to incorporate multiple serums into your routine.
Instead of Layering Your Serums, Rotate Them
Think of your serums like a workout routine—variety will give you the best results, but you wouldn’t want to do all your workouts on the same day or it would lead to fatigue. The same goes for serums. By focusing on one at a time instead of layering your serums, you’ll get the maximum benefit without any interference for a well-rounded approach.
Btw, if you’re reading this and thinking to yourself, “This sounds an awful lot like skincycling,” you’re absolutely right! The concept of rotating your serums in a specific order isn’t new, but the viral #skincycling trend has brought greater awareness to this concept. Since it’s something I’ve been preaching for years, I couldn’t be happier about this.
If you don’t already know, skincycling is a guide to rotating serums in your nighttime routine. A serum schedule, if you will. It’s a great blueprint to follow, but know that skincycling can look different for everyone. For example, not everyone uses a retinol serum, and that’s okay! It’s important to use the ingredients that support your skin type and your skin goals. Those who do use retinol may not be able to tolerate the same frequency of use. It’s all about experimenting a little and figuring out what works best for you. Or, if you’re confused, I always recommend seeking the advice of a skincare professional. Our virtual consultation program makes this accessible to everyone.
How to Rotate Your Serums
Skin is unique (this is the entire philosophy my brand is based on), so not everyone can follow the exact same schedule. That said, this is the general guide I developed as a blueprint. Remember, this is something to build towards—if you’re starting retinol for the first time you’ll want to work your way up slowly.
For nights one and two, use a retinol serum like the Advanced Resurfacing Serum.
Night three is an exfoliating acid serum. The reason I suggest this is that it takes about 48 hours for retinol to increase cell turnover from within and push the old skin cells to the surface. The exfoliating acid serum will help shed those dry, expired cells that are being pushed out by the retinol. This will help manage the surface dryness sometimes associated with retinol use. Again, the type of exfoliating acid serum you use will depend on your skin type and individual needs. To find out which type you need, you can take this Skin Type Quiz.
At the end of the week, a hydrating serum plumps and nourishes those fresh new cells that have been revealed by the combo of retinol and exfoliation. It also gives your skin a rest from actives so that it can rest and repair.
And again, this is just a general guide! Each serum schedule should be tailored to your unique skin.
Look for a Serum With Multiple Beneficial Ingredients
Another sneaky way to get multiple benefits without using multiple products is to find a serum that has more than one beneficial ingredient. What I suggest looking for is a well-rounded serum that will ultimately benefit your skin in more ways than one. For example, these exfoliating acid serums include ingredients like glycerin, allantoin, and aloe to soothe and hydrate, offsetting any potentially irritating effects from the acids. Or, you could look for a retinol serum that includes anti-aging peptides to enhance the overall firming effect of the formula, as well as hydrating ingredients to make it easy to tolerate.
This way, you know everything has been properly formulated to work in tandem and will be able to properly make its way into your skin.
Which Serum Ingredients Should You NOT Combine?
Some ingredients play very well with others while other ingredients very much like to be the star of the show.
Vitamin C (unstable forms like Ascorbic Acid and L-Ascorbic Acid) + Retinol = not recommended. They have different pHs that can conflict with one another.
Vitamin C (unstable forms like Ascorbic Acid and L-Ascorbic acid) + AHAs = can be used together but may cause irritation for sensitive skin types. Proceed with caution.
Vitamin C (stable forms like Magnesium Ascorbyl Phosphate, Ascorbyl Methylsilanol Pectinate, and Tetrahexyldecyl Ascorbate) + AHAs = can safely be used together without the risk of irritation. (But I do recommend using vitamin C in the morning and AHAs at night. Check out the perfect morning routine.)
Retinol + Benzoyl Peroxide = not recommended. Benzoyl peroxide oxidizes easily. Retinol does as well, and it could make them both less effective.
Retinol + Retinol = not recommended to double dose. If you’re using a well-formulated retinol serum, it should engage your retinol receptors to do their job. When you layer on another retinol serum, in an effort to increase the results, you’ll wind up with unnecessary and unwanted irritation.
The Bottom Line
With a plethora of serums and ingredients that can have a positive effect on our skin, it can be tempting to use them all at once. But, this isn’t the best way to maximize results for your skin (or your wallet). First, be mindful that your skin can only absorb so much at one time. Second, remember that layering too many serums or mixing them can dilute their efficacy. Mixing ingredients at home is not like mixing ingredients in a lab! (This is the same reason I’m not a fan of DIY skincare recipes!)
Instead, rotate your serums and try to use just one each night. This will allow the serum to work as effectively as possible without interference so that you get the maximum benefit. It’s all about finding the serums that target your specific skin concerns and creating a schedule that works for you.
Celebrity Esthetician & Skincare Expert
As an esthetician trained in cosmetic chemistry, Renée Rouleau has spent 30 years researching skin, educating her audience, and building an award-winning line of products. Her hands-on experience as an esthetician and trusted skin care expert has created a real-world solution — products that are formulated for nine different types of skin so your face will get exactly what it needs to look and feel its best. Trusted by celebrities, editors, bloggers, and skincare obsessives around the globe, her vast real-world knowledge and constant research are why Marie Claire calls her “the most passionate skin practitioner we know.”