The 10 Best Eyebrow Growth Serums for Full Brows, Tested and Reviewed by Cosmo Editors
All the best formulas for thicker, fluffier brows right this way.
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I know people are loving thin brows as of late, but as a victim of over-plucking and reckless waxing in the 2010s, I always prefer my brows to look thick and bushy, so I can tweeze and shape them from there. And while brow pencils can work to fake the fullness for a few hours, eyebrow-growth serums are the best option to strengthen your brow hairs for the thickest-looking arches with minimal effort.
Cosmo editors have been testing brow serums for months to find the best eyebrow-growth formulas that fill in those pesky bald spots or lengthen brow hairs. “Eyebrow-growth serums won’t necessarily make your brows grow faster or thicker,” says dermatologist Marisa Garshick, MD, “but they can help to strengthen and condition your eyebrow hairs, which may give your hairs a thicker and healthier appearance.” So while a brow serum might not automatically spark new hair growth, it definitely can make the brows look better, prevent hair fall, and create a healthier skin environment to promote hair growth.
To find the best eyebrow-growth serums of all time, we spent years researching and testing dozens of formulas (with the help of trusted dermatologists Dhaval G. Bhanusali, MD; Kavita Mariwalla, MD; and Dr. Garshick).
Our top picks for the best eyebrow-growth serums:
Keep scrolling for the full list of the best eyebrow-growth serums that team Cosmo has tested, along with dermatologist-favorite options. Plus, all of the information on how eyebrow-growth serums work and how to choose the best one for your skin and brows.
Pros
- More budget-friendly than most eyebrow growth serums
- Creates an ideal environment for hair growth
Cons
- May irritate overly sensitive skin
Why we love it: RapidBrow is a strengthening formula loaded with hair-health boosters. Peptides, keratin, moisturizing biotin, and hyaluronic acid are combined alongside a prostaglandin analog (that works to extend the hair-growth phase) to support visible brow growth, while a soothing cocktail of allantoin and licorice root extract keeps skin comfortable. The result is a brow-loving formula that makes brushing your arches up a breeze while promoting healthier, fuller-looking brows over time.
One Cosmo editor says: "I like my brows to be fairly thin—a bushy brow next to my ultra-fine head of hair would look a lil strange—but I do have some sparse areas that I would love to fill out. I've been swiping on RapidBrow to help fill that in, but it's grown my brows so. freakin'. much. I am tweezing so much more often than ever to keep up with my shape, but really loving how thick my brows feel. I still have my thin look, but a softer, healthier-looking brow overall."—BETH GILLETTE, BEAUTY EDITOR
Features at a Glance
| Key ingredients | Peptides, keratin, biotin, isopropyl cloprostenate (prostaglandin analog) |
| Hormone-free? | No |
| Application frequency | Twice daily |
Pros
- Spoolie applicator makes it easy to style brows with the serum
- Works faster than any of the other options on this list
Cons
- Might leave behind some temporary redness around the brows, but it goes away in a few hours
Why we love it: This formula is packed with hair-boosting ingredients that helped me grow super bushy brows in just two months—check out my photos below for the proof. Whether you’re filling in sparse areas or aiming to lengthen brow hairs overall, biotin, panthenol, and hyaluronic acid work alongside a prostaglandin analog, a hair-growth-stimulating active similar to those used in prescription serums, to support follicle activity and promote fuller, thicker-looking brows over time.
One Cosmo editor says: "I have never had a brow serum work so well in my entire life. After a waxing experience years ago that completely botched my brows, I've been working to get back my shape and thickness ever since. I probably tweeze once or twice a year at most, but after just a few months of testing this formula, my sparse brows turned so bushy and soft, I'm growing new hairs where I never have before, and even the length of my existing hairs are requiring a trim—I can't remember the last time I've needed to cut my brows down. I've tried brow serums for years, but this one is the clear winner if you're willing to splurge in the name of brow thickness."—JASMINE HYMAN, ASSISTANT BEAUTY EDITOR
Features at a Glance
| Key ingredients | Biotin, dehydrolatanoprost (prostaglandin analog) |
| Hormone-free? | No |
| Application frequency | Once at night |
Pros
- Free of any skin-irritating ingredients
- Our testers saw a difference in sparse areas in just a couple months
Cons
- Applicator isn't the best for combing through each brow hair
Why we love it: We're huge fans of Vegamour's lash serum, and the brow serum is similarly formulated with nourishing plant-based ingredients like magnolia bark, clover sprout, and flower extracts, alongside biotin-like peptides that support follicle health and strengthen hairs. Completely vegan and free of hormone-like actives, it helps gently fill in sparse areas over time, leaving brows looking fuller and healthier, without any irritation.
One Cosmo editor says: "I had a few stubborn sparse spots on my arches and some funkiness around the cowlick on my right brow. However, after using Vegamour’s serum for over a month, I’ve completely given up filling in my brows. They’re thicker and more even than they’ve been in years. The doe foot makes application a breeze and the quick-drying formula allows me to start my makeup almost immediately after. I have very sensitive skin and have experienced zero irritation. It takes me two seconds to apply this twice a day, and I’ve never felt more confident in my eyebrows."—JAYNE LEMIRE
Features at a Glance
| Key ingredients | Peptides, clover sprout, magnolia bark |
| Hormone-free? | Yes |
| Application frequency | Twice daily |
Pros
- Can also double as a sculpting brow gel
- Uses signature protein complex to strengthen brows
Cons
- Might run out quickly if you use morning and night
Why we love it: This brow serum from Olaplex uses the same bond-building technology found in their protein-packed haircare. It’s loaded with hair-strengthening peptides, as well as biotin, panthenol, and hyaluronic acid to hydrate and nourish hairs. Plus, oat and clover flower extracts soothe and condition the skin underneath to avoid irritation. The result is a formula that strengthens, protects, and encourages healthier brow growth with every use.
One Cosmo editor says: "This brow serum was a breeze to apply thanks to a doe foot applicator—kinda like a lip gloss—and a gel-like consistency that was comfortable to wear and dried quickly. I didn't notice any irritation or burning, even though my skin is pretty sensitive. It definitely made my existing brow hairs grow longer more quickly, and I noticed less fallout than usual, but I haven't noticed a ton of new growth. Since it's so pleasant to apply, I plan to keep using it to see if it makes more of a difference over time."—LAUREN GRUBER, ASSOCIATE COMMERCE EDITOR
Features at a Glance
| Key ingredients | Peptides, biotin, hyaluronic acid |
| Hormone-free? | Yes |
| Application frequency | Morning and night |
Pros
- Helps hydrate and soften the hairs while also promoting growth
Cons
- While the applicator is good for targeting small areas, it's tough to comb through the brows
Why we love it: Anastasia Beverly Hills is beloved for its brow gel products, which have become a staple for anyone craving perfectly sculpted, long-lasting brows. The brand also has this brow serum, designed to support fuller, stronger brows over time. The formula is packed with hair-loving ingredients: castor oil, peptides, clover extract, and panthenol condition and strengthen each strand to encourage a health environment for hair growth.
Plus, it’s got antioxidant-rich caffeine, that has anti-inflammatory properties to help calm down irritation, which dermatologist Dr. Bhanusali, MD, notes can reduce hair fall.
One Cosmo editor says: “I already have fairly thick eyebrows, but I was hoping to apply it to some of the gaps I usually fill in. The serum works well, and I saw major hair growth where the follicles were already active. I also noticed some areas where I didn’t directly apply the serum were growing at a faster rate too. The results were noticeable but not drastic for me. It dries fairly quickly, and the formula did not irritate my sensitive skin.”—KHADIJA HORTON, SENIOR DESIGNER
Features at a Glance
| Key ingredients | Castor oil, peptides, caffeine, red clover extract |
| Hormone-free? | Yes |
| Application frequency | Twice daily |
Pros
- Precise applicator
- Eliminates the need for a brow pencil
Cons
- We wish it came in a blonde hair-friendly shade
Why we love it: This two-in-one brow serum tints and fills in brows while helping them grow over time. It’s formulated with hair-nourishing ingredients like vitamin E, panthenol, and castor oil, which work alongside a prostaglandin analog to promote brow growth. So instead of needing a brow pencil, gel, and serum, you could use this every morning instead!
One Cosmo editor says: I was pleasantly surprised by the growth I saw after using this brow serum. I was quickly impressed by its lightweight formula, it never felt heavy or sticky, and I loved the subtle tint—it added instant color and fullness, making a noticeable difference for my thinner brows and perfect for everyday glam when I just wanted to fill them in, and the thin brush applicator made application easy and precise. After using it consistently, I did see a difference—nothing dramatic, but visible. Overall, it felt like a natural, gradual enhancement and I imagine they’ll thicken even more in the next weeks/months."—MEG UY, SHOPPING EDITOR
Features at a Glance
| Key ingredients | Castor oil, vitamin E, isopropyl cloprostenate |
| Hormone-free? | No |
| Application frequency | Once daily |
Pros
- Uses max-strength ingredients to help brow hairs grow
Cons
- Have to get a prescription, which can be $$$
Why we love it: Latisse is currently the only eyelash serum approved by the FDA for lash growth, but derms, like Dr. Bhansuali, also recommend it to help grow out your brow hairs. How does it work? Well, it’s formulated with an active ingredient called bimatoprost, which helps lengthen the growth phase of your hair so that they have more time to grow before falling out, leading to thicker, fluffier brows over time.
Just swipe it across your brows with the included applicator once a day, and you should start to notice some thickness in four to six weeks. But keep in mind that Latisse is strong, so there can be side effects, like skin irritation. Make sure to discuss the potential risks with your doctor (whether you go in-person or try a telemed service like Ro or Nurx). Read Cosmo's full review on Latisse here.
- Key ingredients: Bimatoprost (promotes hair growth)
- Recommended use: Daily at night for 16 weeks
- Size: 0.1 fl oz.
One Cosmo editor says: “My lashes are noticeably darker, thicker, and longer, and when I really started to think about it, my lashes have looked a lot better the last month or so. You can see the individual lashes fan out across my lid in a really girl-ish, beautiful way. I love the way they look."—DANIELLE COHEN, CONTRIBUTING WRITER
| Key ingredients | Bimatoprost (promotes hair growth) |
| Hormone-free? | No |
Pros
- Applicator is great for targeting sparse spots
- Completely plant-based
Cons
- The thin brush is tough to go through the entire brow
Why we love it: We crowned this brow serum the best of the year in our annual Holy Grail Awards. Formulated with plant-based extracts like castor oil and jojoba oil, it strengthens each brow hair without irritation or any hormone-esque ingredients.
One Cosmo editor says: “This extra-thin brush applicator makes it possible to precisely target actual eyebrow hair follicles versus the usual spoolie or doe-foots that I’m used to. Albeit minor, I noticed almost immediate results within my first week of use (shiny, healthy-looking brow hairs). After about three weeks, my brow hairs appeared darker and longer, and after about five weeks, I noticed a fuller brow shape with baby hairs sprouting up near my arch. I doubly appreciate these impressive results considering there are only five ingredients in the formula—all of which are natural oils. No skin irritation for me!” —HANNAH OH, SHOPPING EDITOR
Features at a Glance
| Key ingredients | Castor oil, jojoba oil |
| Hormone-free? | Yes |
| Application frequency | Once daily |
Pros
- Helps moisturize dry skin and hair
- The most affordable option on this list
- Derm-loved
Cons
- Some testers say it left a residue on their brows
Why we love it: Got dry skin? Dermatologist Dr. Garshick recommends The Ordinary’s eyebrow-growth serum that’s filled with peptides to moisturize not only your brow hairs, but the brow skin itself, while also strengthening your skin barrier over time (and we know, moisturized hair = better chance at healthy hair growth).
| Key ingredients | Peptides, caffeine |
| Hormone-free? | Yes |
| Application frequency | Twice daily |
Pros
- Derm-loved
- Comes in a travel size as well
Cons
- May cause temporary irritation
Why we love it: Both dermatologists Marisa Garshick, MD, and Kavita Mariwalla, MD, like this simple eyebrow-growth serum as a moisturizing option that’s still lightweight (see: the ingredients list without heavy oils and butters). “This formulation incorporates peptides, lipids, panthenol, and biotin to condition brows, along with calendula, which serves as a humectant to draw moisture in,” says Dr. Garshick.
And not only is it derm-loved, but our readers and team Cosmo are huge fans of the nourishing formula, too. So much so that the lash version has won two Cosmo seals of approval—a Readers' Choice Award and a Holy Grail Award.
Features at a Glance
| Key ingredients | Biotin-peptide complex, panthenol, cloprostenol ethyl amide (a prostaglandin analogue) |
| Hormone-free? | No |
| Application frequency | Once a day |
Do eyebrow growth serums actually work?
Eyebrow serums can be effective, but results depend on the ingredients and consistent use. Many serums use peptides and vitamins, which help strengthen hairs, nourish follicles, and support overall brow health, leading to fuller, stronger brows over time.
Some serums contain prostaglandin analogs, which are hormone-like compounds that extend the hair growth cycle, promoting hairs to grow longer and thicker. Plant-based formulas may take a little longer to show results, while prostaglandin-filled serums often deliver faster, more noticeable growth.
For best results, daily application over several weeks to a few months is recommended. Keep in mind that serums enhance existing follicles—they cannot generate hairs where follicles are inactive.
How do eyebrow growth serums work?
“Most of the latest nonprescription brow serums are designed to improve the thickness of each brow hair and, depending on the formula, can maybe even improve growth,” says board-certified dermatologist Kavita Mariwalla, MD.
Basically, they can make your eyebrow area a healthier, happier place, which, in turn, can encourage even better eyebrow growth. Still, don’t expect overnight results: Dr. Mariwalla explains that you could be waiting anywhere from three to six months before you notice any visible changes.
How often should you use eyebrow serum?
How often you should use your eyebrow serum fully depends on the product you’re using. Read the directions for your specific serum (some require twice-daily use, while others can be brushed on once a day). Generally, though, Dr. Bhanusali recommends swiping on your eyebrow serum once a day at night before smoothing on your moisturizer.
How long does it take for eyebrow serum to work?
How long it takes for eyebrow serum to “work” depends on the type of serum you’re using. A product with active, growth-inducing ingredients—like prescription-only bimatoprost, and over-the-counter prostaglandin analogs—can help potentially grow your eyebrow hairs in six to eight weeks when brushed on daily. But if you’re using a serum that’s filled with good-for-skin ingredients (like: hyaluronic acid, peptides, aloe, amino acids), you’ll hopefully see some thickness over three to four months with daily or twice-daily use.
Jasmine Hyman is the Assistant Beauty Editor at Cosmopolitan, where she writes about the latest beauty trends and must-have products. Her most prized beauty possessions are a meticulous skincare routine and salon blowouts. You’ll also likely find her in bed reading a good book or endlessly scrolling TikTok (spoiler: it’s usually the latter) while listening to Harry Styles’ entire discography on repeat. Follow her on Insta to be inundated with pictures of her meals.
Beth Gillette is the beauty editor at Cosmopolitan, where she covers skincare, makeup, hair, nails, and more across digital and print. She can generally be found in bright eyeshadow furiously typing her latest feature or hemming and hawing about a new product you "have to try." Prior to Cosmopolitan, she wrote and edited beauty content as an Editor at The Everygirl for four years. Follow her on Instagram for makeup selfies and a new hair 'do every few months.
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