This is the best vitamin C serum of 2025 — it’s potent, innovative and long lasting
Of all the skin care ingredients I test as a beauty editor, vitamin C serums are my favorite. I find they have the greatest impact on the clarity and tone of my 52-year-old skin, especially when I’m using a high-quality product. I interview dozens of dermatologists and aestheticians each year, and most every expert I talk to recommends the same skin care regimen: daily SPF, moisturizer, retinol and regular use of a vitamin C serum to bolster healthier, younger-looking skin. “A vitamin C serum is nonnegotiable. You need it twice a day,” explains facial plastic surgeon Dr. Kay Durairaj. “In the morning, it’s an antioxidant to treat sun damage; in the evenings, it’s going to help build collagen and skin repair.”
This is my third year testing the best vitamin C serums, but it’s the first where there’s been a seismic shift in the category. In March, L’oreal, the company that owns Skinceuticals, allowed the patent on the brand’s cult-favorite C E Ferulic serum to expire, leaving the path open for competitors to replicate its iconic formula. This is significant because, for a long time (upwards of 20 years!), the Skinceuticals C E Ferulic was the only vitamin C serum that experts agreed was worth recommending. Its mix of ingredients and PH levels was commonly considered the best, if not the only, effective vitamin C serum game in town.
But now? More and more skin care brands are throwing their hats in the vitamin C ring, mixing ingredients that are a close, if not quite identical, match to the original. This year, I tested a half a dozen of these newer competitors, along with a handful of new-to-me consumer favorites. After all this, I felt sure I’d uncover a new winner in this category — but was surprised to come back to my original favorite. Here’s why.
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Update, September 18, 2025: We checked all product prices and availability. Our No. 1 pick for best vitamin C serum remains unchanged.
The best vitamin C serum for 2025
Drunk Elephant
Benefits: Brightens skin and dark spots, reduces appearance of sagginess and fine lines, gives skin a “glow” | Vitamin C potency: 15% | Skin Type: Any, but may be too harsh for the most sensitive skin | Dosage: A few drops in the morning | Size: Just over 1 ounce in combination of serum and powder | Cruelty Free: Yes
Ringing in at less than half the cost of Skinceuticals C E Ferulic, Drunk Elephant’s C-Firma Fresh Day Serum is a high-quality, highly effective alternative. I love it for all sorts of reasons — including the fact that, when I re-tested it last month, it almost immediately lightened new summer dark spots on my cheeks, noticeably tightened my skin and consistently gave my complexion a pretty, brighter glow.
But what makes C-Firma superior to nearly any competitor is the unique way it’s packaged: The formula arrives in two parts — a liquid serum along with an accompanying vial of pristine vitamin C powder. You mix the two just before your first use, maximizing the stability of the vitamin C molecules and thus ensuring freshness. Once mixed, the product remains potent for three to six months, depending how you store it (i.e., preferably in a cool, dark place, like a cabinet).
And there’s more to love: C-Firma contains ferulic acid and vitamin E, both of which boost its efficacy. The balance of ingredients here is near identical to C E Ferulic — in fact in 2018, L’oreal sued Drunk Elephant because this recipe was too close to Skinceuticals’s original formula.
Reviewers also like C-Firma’s easy-to-use/easy-to-travel-with bottle, which includes a convertible pump. The serum inside is lightweight and absorbs quickly, though the texture may feel a bit a sticky for some. Finally, it’s potent — it may even sting your skin a bit.
As compared to Skinceuticals C E Ferulic, Drunk Elephant’s C-Firma gains points for being both cruelty-free and free from a foul odor (C E Ferulic has a deeply unpleasant scent). While many beauty influencers still claim that the original C E Ferulic is the only vitamin C worth buying, keep in mind that it’s also $182 for just one ounce, making it inaccessible for most bank-account-having humans, at least for long-term use. (I don’t care if it’s made of gold, I am not spending that kind of money on something to dab on my face — and I don’t think you should have to either!)
At $79, C-Firma is not exactly a steal, but the formula (plus the effect on your skin) is top-notch. My first bottle lasted four months with twice-daily use, so a little goes a long way.
- Highest-quality ingredients
- Innovative packaging means the product stays fresher longer
- Brightens skin
- Improves texture of aging skin
- Lightweight
- Absorbs quickly
- Some may find the texture sticky
- May be too harsh for the most sensitive skin
$79 at Amazon
Other top vitamin C serums we recommend
Amazon
Benefits: Brightens skin and dark spots, reduces appearance of sagginess and fine lines | Vitamin C potency: 20% | Skin Type: The high concentration of vitamin C may be too harsh for sensitive skin | Dosage: A few drops in the morning | Size: 1 ounce | Cruelty Free: Yes
When the patent on Skinceuticals’ formula expired in March, it cleared the path for much less expensive swaps, like this one from Dr. Brenner, which utilizes L-ascorbic acid, ferulic acid and vitamin E just like the Skinceuticals original.
What’s improved here is the addition of calming and hydrating hyaluronic acid. I found Dr. Brenner’s serum to be less drying to my skin than many I tested at this price point and — while it didn’t work quite as well as my top pick — it still provided real skin-brightening value, especially for the cost.
Also unique here is the production of the serum itself. The company is actually a small cosmeceutical development lab that creates all of its products in collaboration with dermatologists and cosmetic chemists. They work in small batches to make their serums — a new batch is produced every two weeks to ensure product freshness.
- Affordable
- Potent well-balanced formula
- High vitamin C percentage balanced by soothing hyaluronic acid
- Contains vitamin E and ferulic acid
- Brightening effect slightly less than our top pick
- Scent is less-than-pleasant
$24 at Amazon
Timeless Skin Care
I’m honestly splitting hairs between Timeless’s vitamin C and Dr. Brenner’s. They both smell and feel about the same, and have similar ingredients, I slightly prefer the Dr. Brenner serum as I found the Timeless serum a tad more irritating and drying, but, in the interest of public service beauty journalism, I’ll tell you: the internet doesn’t agree with me.
There’s an entire worldwide web of vitamin C-serum-heads debating individual products’ pH levels and the inferiority of C-derivatives like sodium ascorbyl phosphate over the gold-standard L-ascorbic acid. However, once you get DEEP into wonky skin-care Reddit, you’ll find heaps of praise for this one by Timeless.
It’s lightweight, absorbs quickly, is for sure less sticky than C-Firma and contains the right percentage of the main ingredient, combined with vitamin E and ferulic acid. Timeless’s version also boasts more than 6,000 exuberant 5-star reviews on Amazon, all repeating something along the lines of this one: “OMG!! Someone finally did Vitamin C RIGHT, and they’re NOT charging 100’s of $$ per ounce!!”
- Affordable
- Well reviewed
- Less sticky than our top pick
- We found the formula to be slightly less potent than our top pick
- Shelf life is shorter than our top pick
- Some found the formula drying
$26 at Amazon
Amazon
Benefits: Brightens skin and dark spots, reduces appearance of sagginess and fine lines, gives skin a “glow” | Vitamin C potency: 12% | Skin Type: Gentle enough for most skin | Dosage: A few drops in the morning | Size: Just over 1 ounce in combination of serum and powder | Cruelty Free: Yes
Of the many serums I tested, this version from Vitabrid is among the most impressive. Like C-Firma, the formula arrives in two parts — a liquid serum along with an accompanying vial of vitamin C powder. You mix the two just before each use, which, of course, maximizes the stability of vitamin C molecules and ensures you’re using the freshest product possible. Once mixed, the two components form one slightly grainy emulsion that absorbs quickly into your skin and is scent-free — a rare quality and unlike most any vitamin C skin care I’ve tried.
Vitamin C is an “active” ingredient that can be harsh for some skin types. The selling point to the Vitabrid version is it uses a proprietary ingredient designed to release vitamin C gradually over 12 hours, offering the skin-brightening benefits of the hero ingredient (ascorbic acid) while remaining more gentle on the skin.
The serum itself is infused with niacinamide and copper peptides, and the entire package made my skin look clearer, brighter and even a little tighter over the course of 30 days of use. If your skin is sensitive and you still want to use a potent vitamin C, this is for you.
- Releases vitamin C gradually to the skin over 12 hours
- Gentle and safe for most skin types
- Fragrance free
- Fast absorbing
- No sticky residue
- Lacks vitamin E and ferulic acid
- Mixing the powder and serum together each night is inconvenient
$32 at Amazon
How we tested vitamin C serums
Our top pick from Drunk Elephant comes in two parts — a serum and a separate powder — which you mix before first use ensuring freshness. (Jennifer Romolini/Yahoo)
Vitamin C is an extremely unstable molecule that degrades rapidly when exposed to elements like sunlight or heat. This means you should look for packaging (like opaque plastic or dark-colored glass) that will hold up in transit and, later, storage. You also want to guarantee the product inside is “fresh” (more on this in my review above). Remember, in most cases, vitamin C is most effective in tandem with ferulic acid and vitamin E, so before making any new purchase, study labels. Last, a serum with less than 10% concentration of vitamin C will not reap the skin-brightening, collagen-boosting benefits you want. On the flip side, more is not more: Over 20% concentration will irritate most skin types. The sweet spot here is somewhere in between.
When I set out to test vitamin C serums, I limited my scope to those that met most all of the qualifications above. I also stuck to products that implemented the vitamin C derivative L-ascorbic acid, since this has been clinically proven to yield the best results.
I then tested each product for efficacy over the course of at least two months. Once I knew a particular product had the desired effect on my skin, I took the following into consideration:
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Texture and skin feel: Did it feel tacky on my skin? Was the product uncomfortable to use?
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Absorbency: Did the product sink in? Did it leave a residue?
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Scent: Was the scent appealing or at least tolerable?
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Value: Were the results worth it for the cost?
Vitamin C serums we tested that didn’t make the cut
We tested a dozen vitamin C powders, creams and serums from an array of popular brands. (Jennifer Romolini/Yahoo).
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SkinCeuticals‘ C E Ferulic: The most viable alternative to Drunk Elephant’s C-Firma is, of course, this popular product. Let me say upfront that I like it — a lot. It also brightened my skin, helped with rough texture and gave me a glow overall. But I don’t like its scent, which is putrid. I found the texture to be too sticky and — at nearly $200 — I could never justify the cost.
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I found Sunday Riley’s CEO to be more of a moisturizer than a vitamin C serum and, while it did leave my face hydrated, it did little to bright my skin.
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Paula’s Choice C5 Super Boost Eye Cream was harsh, made my skin uncomfortably sting and was, therefore, unusable in my undereye area. After a month of nightly use, I saw few results.
Vitamin C serum FAQs
What does a vitamin C serum do?
“Vitamin C is an antioxidant. Antioxidants are substances that can protect, prevent or delay cellular damage by counteracting the free radicals and oxidative stress caused by environmental pollutants, UV rays, chemicals and other factors,” says Beverly Hills cosmetic dermatologist Dr. Ava Shamban. “Vitamin C is perhaps our most important antioxidant, it can boost brightening, improve hydration, reduce the appearance of wrinkles and hyperpigmentation and fight inflammation.”
Unlike with many popular beauty ingredients, vitamin C’s skin-health benefits have been extensively researched. Studies show that consistent, daily use of a stable form of vitamin C improved skin texture and evened skin tone on both the face and neck (results were seen in as little as three months). In clinical trials, vitamin C serums were shown to reduce hyperpigmentation from sun damage, lighten dark spots and diminish redness, particularly if the formula had a concentration of 10% to 20% vitamin C and contained stabilizing ingredients like ferulic acid and vitamin E.
When is the best time to use vitamin C serum?
Experts are mixed on whether the antioxidant product is best used when you first wake up or before bed, but according to Durairaj, either — or both, to maximize efficacy.
How often should I use vitamin C serum?
Vitamin C is among the most potent and beneficial ingredients for maintaining healthy skin — if your skin can tolerate it, apply every day, at least once. If you find the ingredient irritating, try every other day to start and then build up over time.
How to apply vitamin C serum?
Whether you choose morning or evening application, for the greatest benefit, vitamin C should be the first step in your skin-care routine after cleansing. Pat on a few (two to three) drops or pumps on a freshly washed face.
Will vitamin C serum protect my skin from the sun?
This is a resounding NO! If you’re going to be outside during the day, always apply a high-quality, broad-spectrum sunscreen with SPF 30 or higher.
Meet the experts
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Beverly Hills cosmetic dermatologist Dr. Ava Shamban
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Board-certified facial plastic surgeon Dr. Kay Durairaj
The reviews quoted above reflect the most recent versions at the time of publication.
We received complimentary samples of some products and purchased others ourselves, but we reviewed all products using the same objective criteria.