Everyone Compliments My Eyelashes—And It's All Thanks to This Serum (2025)

"Eyelash growth serums and lash conditioners may help strengthen lashes, prevent them from breaking, or lightly swell them so they look a little thicker,” says ophthalmologist Ilyse Haberman, MD. No, they won't necessarily make them actually grow longer (only prescription Latisse can do that, FYI), but some eyelash growth serums can make your lashes thicker and less prone to falling out, which is something!

As a full-on eyelash-growth serum convert, I've tested countless eyelash-growth serums, Here’s a peek at some of my holy grails (plus a bunch of favorites from other Cosmo editors):

Legit, every facialist and makeup artist who has the ~pleasure~ of getting close to my face compliments how thick my lashes are—and it’s all thanks to swiping on GrandeLash for the last four years. It uses L-proline, an amino acid, to help strengthen my lashes, along with hyaluronic acid and aloe vera to help hydrate them. So although it doesn’t necessarily make my lashes grow longer, it does make them so much more voluminous and soft, which I’ll happily take. It also features both hyaluronic acid and aloe vera to help hydrate my lashes, which is great for making them look more fluffy and thick.

• Key ingredients: L-proline, hyaluronic acid, aloe vera, isopropyl cloprostenate (prostaglandin analog that can possibly help thicken lashes)
• Hormone free? No
• Application frequency: Once a day
• Size: 0.03 fl oz

One Cosmo editor says: "Out of all the different lash-enhancing serums I’ve tried over the years, GrandeLash has repeatedly given me the best results. Without fail, I know that my lashes will look longer, become more dense, and feel softer after just a few months." — Mary Honkus, beauty contributor

Latisse is currently the only eyelash serum FDA-approved for lash growth. It’s formulated with an active ingredient called bimatoprost, a prescription-only prostaglandin analog that helps grow your existing lashes and stimulate the growth of new hairs in four to six weeks. But keep in mind: It’s pretty strong, so make sure to discuss the potential risks—like eye irritation, eye-color change, and eyelid-darkening—with your doctor beforehand, says ophthalmologist Nicky Shah, MD.

• Key ingredients: Bimatoprost (prostaglandin analog that can help grow lashes)
• Hormone free? No
• Application frequency: Once a day
• Size: 0.17 fl oz

One Cosmo editor says: "I love the results. My eyelashes just look better. So much so that I plan to keep the habit up for my wedding in June." — Danielle Cohen, beauty contributor

FYI: Sydney Sweeney says she ordered this lash serum after seeing it on TikTok (Celebs! They’re just like us!), and said that makeup artists don’t even put false lashes on her anymore because her lashes have gotten so voluminous and fluttery. The serum contains isopropyl cloprostenate (a synthetic prostaglandin analog) that can help lengthen the growth phase of your lashes, along with conditioners like peptides, hyaluronic acid, soybean oil, and biotin for softer and healthier lids and eyelashes. And it's frequently on sale, so win-win.

• Key ingredients: Peptides, hyaluronic acid, soybean oil, biotin, isopropyl cloprostenate (prostaglandin analog that can possibly help thicken lashes)
• Hormone free? No
• Application frequency: Once a day
• Size: 0.1 fl oz

One Cosmo editor says: "As a beauty editor, I've tried my fair share of lash serums, but I always find my way back to Rapid Lash. After using the formula for months, I noticed such a difference in my lash length (and strength!). Other serums have irritated my eyes, but this one is gentle enough to use every night before bed. I also love the corresponding brow serum to brush through my hairs whenever I use the lash one." — Jasmine Hyman, assistant beauty editor

Eyelash serums are notoriously filled with ingredients that can be pretty irritating for your sensitive lil bb eyes. But this one is fully clean (even by Cosmo Clean Beauty Awards standards), using mostly peptides to help strengthen and nourish the heck outta your lashes to make them less likely to fall out. Don't expect this to make your lashes necessarily grow (tbh, most serums won't do this anyway), but it can help encourage some thickness over time.

• Key ingredients: Peptides, mung bean extract
• Hormone free? Yes
• Application frequency: Once a day
• Size: 0.1 fl oz

One Cosmo editor says: "I was not blessed with my mother’s beautiful long lashes, so I was super hopeful this would help my lashes look thicker. I noticed my lashes curl much easier and actually stay curled for most of the day, even without mascara." — Joanna Marquina, social media growth editor

A blend of strengthening peptides and moisturizing biotin, hyaluronic acid, and sodium PCA make this a super impressive cocktail for conditioning your lashes. Reminder: Your best bet for better-looking lashes is healthier lashes. The key here is to consistently swipe this on every night before bed to help slowly fluff things up.

• Key ingredients: Peptides, biotin, hyaluronic acid, sodium PCA
• Hormone free? No (but contains much less than other serums, FYI)
• Application frequency: Once a day
• Size: 0.1 fl oz

One Cosmo editor says: "I've been using BabeLash for years now—so much so that I turned my mom on to it and now we are both obsessed. It's also my go-to stocking stuffer. It's easy to use, doesn't irritate my eyes, and best of all: It actually works, IMO! My naturally short, sparse lashes are noticeably longer thanks to this, which makes curling and applying mascara more rewarding." — Mackenzie Dunn, senior commerce manager

I already have enough products in my bathroom (sry, roomie), so I was stoked to try this eyelash serum that I could use to help make my brows a little bushier too. It won’t make your lashes or brows necessarily longer, but it’s hella moisturizing and soothing, thanks to its aloe vera and cannabis-seed extract (which is a great anti-inflammatory, btw). Milk’s serum is also packed with peptides to help moisturize and help strengthen your lashes and brows to limit hair fall. Swipe it along your upper and lower lash lines, then draw short, hair-like strokes through your brows as the final step of your nighttime skincare routine.

• Key ingredients: Peptides (moisturizing); aloe vera, cannabis seed extract (moisturizing and soothing)
• Hormone free? Yes
• Application frequency: Twice a day
• Size: 0.12 fl oz

One Cosmo reader says: "It takes time for the results to show, but this is great! My aesthetician has mentioned how much longer my lashes are since I started using it. I’ve been using the serum for about two years now."

But Olaplex’s eyelash serum actually uses a bond-building ingredient instead to help thicken and strengthen my lashes. It helps rebuild the bonds in my lashes to make them stronger and less prone to hair fall, which inevitably makes them look thicker over time. After lining my upper lid with this serum twice a day for three months, my lashes feel ultra-soft too.

• Key ingredients: Bis-aminopropyl diglycol dimaleate (bond-building), peptides (strengthening)
• Hormone free? Yes
• Application frequency: Twice a day
• Size: 0.15 fl oz

One Cosmo editor says: "This seriously made my eyelashes feel so much stronger after six months of consistent use. I'm so used to my eyelashes feeling crunchy and brittle—too many coats of mascara in my youth, lol—but this basically brought them back to life." — Beth Gillette, beauty editor

If you’re perusing the drugstore aisles for an eyelash serum, don’t skip over Neutrogena’s. It’s full of biotin and peptides, which doesn’t actually enhance hair growth but does add a nice coating to help your lashes appear softer and fuller. So if your lashes feel like they’re on the finer side, this moisturizing serum might give your lashes a thicker appearance for less than the cost of happy-hour drinks.

• Key ingredients: Biotin, peptides (moisturizing)
• Hormone free? Yes
• Application frequency: Once a day
• Size: 0.08 fl oz

One Cosmo reader says: “I noticed that the eyelashes that I do have stopped breaking off and falling out after about a week. It truly moisturizes your upper and lower lashes so that when you remove even stubborn waterproof mascara, you don't lose eyelashes."

The only eyelash serum that “works” for growth is Latisse, which is the one and only FDA-approved eyelash serum that has been scientifically proven to encourage eyelash growth. It works by enhancing the growth phase of your lashes (FYI: hair has a growth phase, a resting phase, and a shedding phase), says Dr. Gohara. What Latisse does—or, specifically, what its active ingredient called bimatoprost does—is help stretch the timeline of the growth phase, so your lashes can grow longer before they naturally fall out (the shedding phase).

But whether or not over-the-counter eyelash serums “work” for hair growth, the answer would be no—or at best, maybe. According to Dr. Gohara, most eyelash serums will condition and support the keratin in your lashes, kind of like a conditioner, explains Dr. Haberman.

Just note that if you’re experiencing major lash loss, you should first see your doctor to figure out what’s causing the hair loss before stocking up on a lash serum, says Dr. Gohara. Eyelash loss can be caused by a host of factors, including alopecia, medication side effects, age, and certain disorders. When in doubt (or anxiety), head to your dermatologist.

Lash serums can potentially have side effects, says Dr. Shah, especially if they contain prostaglandin analogs (a compound that mimics the hormone found naturally in our bodies that stimulates hair growth), which can possibly darken your eyelids and cause puffiness and irritation around your eyes. Dr. Shah also notes some patients have experienced darkening of their iris, as well as a “sunken” look to their eyelids over time (though both of these effects have currently only been studied with bimatoprost, the prescription-only prostaglandin analog).

Luckily, Dr. Shah notes that these side effects typically go away after stopping use. All of this to say, you should definitely see your doctor before you start using a lash serum, especially if you have dry, sensitive eyes (i.e., you can barely put on mascara without tearing up or getting itchy eyes) or wear contact lenses, which sometimes can cause dry eyes.

Latisse is considered the “best” eyelash-growth serum on the market, as it’s the only serum that’s FDA-approved to actually grow your lashes. It uses an active ingredient called bimatoprost, a compound derived from prostaglandin analogs (a family of fatty acids) that mimic your body’s natural hair-growth hormones. Bimatoprost—and prostaglandin analogs in general—work to extend your hair’s growth phase, meaning your lashes have more time to grow before they fall out, resulting in thicker, longer lashes.

Here’s the thing: Although no other lash serum uses bimatoprost specifically, many lash serums do contain other prostaglandin analogs (like isopropyl cloprostenate, isopropanol Phenyl-hydroxyl-pentene, dihydroxy-cyclopentyl-heptenate, and dehydrolatanoprost), which are thought to help grow and thicken your lashes like bimatoprost—though research is still lacking on their exact efficacy. Still, just because they haven’t been studied doesn’t mean they aren’t effective to some extent.

And if you don’t like the idea of using a lash serum with active ingredients, you can always try a conditioning formula that works to keep your lashes moisturized, healthy, and shiny. These serums are typically spiked with hyaluronic acid, peptides, and castor oil, which are all great for conditioning and potentially plumping your lashes, but won’t necessarily make them longer. So if you’re looking for true eyelash growth, Latisse is your best bet, followed by an eyelash serum with prostaglandin analogs.

Figure out your eyelash goals

Do you have super-short, barely there lashes that you really want to thicken up? Consider Latisse, which is the “best” lash serum for growing thicker, longer lashes if you use it consistently for three or four months. Or you can try another eyelash growth serum with a prostaglandin analog, which is more likely to help increase lash thickness when compared to prostaglandin-free formulas.

However, if you’re just looking to moisturize or strengthen dry, brittle lashes, opt for an eyelash serum with ingredients like hyaluronic acid, peptides, and oils like castor oil and jojoba oil that will coat your lashes to make them appear thicker and denser with use (and with a lower risk of irritation).

Consider the application requirements

If you just know you can’t be held accountable to brush on an eyelash serum twice a day for six months, choose a serum that’s easier to incorporate consistently, like an eyelash serum primer, a lash-conditioning mascara with moisturizing peptides, or one that’s already mixed into your eye serum at night.

FWIW, Dr. Shah recommends incorporating an eyelash serum for a few months to see results, then cutting back to once or twice a week to maintain the thickness. Meaning if you can tolerate lining your lash line with eyelash serum every night for three to four months, you’ll get faster results that you’ll only have to maintain afterward.

• Nicky Shah, MD, is a board-certified ophthalmologist in Brooklyn, NY. She’s the founder of skincare brand You & Eye, which features moisturizing and soothing eye and lash treatments.
• Mona Gohara, MD, is a board-certified dermatologist at her own practice in Hamden, CT. Dr. Gohara is an associate clinical professor at Yale School of Medicine and president of the Women’s Dermatologic Society. Her areas of expertise include medical and surgical dermatology and skin of color.
• Ilyse Haberman, MD, is a board-certified ophthalmologist at NYU Langone Health, and an assistant professor of ophthalmology at NYU Grossman School of Medicine.
• Courtney Buhler is the founder and CEO of Sugarlash ProR, a line of eyelash products like false eyelashes, lash lift solutions, and lash extensions.

Beth Gillette is the beauty editor at Cosmopolitan with five years of experience researching, writing, and editing hair and skincare stories that range from under-eye bag treatments to hair-growth vitamins. She’s an authority in all skincare categories, but is an expert when it comes to eyelash serums, thanks to years of testing them on her own fine eyelashes. She regularly tests and analyzes eyelash serums for efficacy, while working with the industry’s top dermatologists and ophthalmologists to assess new formulas and brands.

Sarah Maberry is a commerce writer at Hearst Magazines with over four years of experience researching and writing skincare, hair and makeup stories. Her eyelash serum picks were based on market research, ingredient safety analysis using EWG's Skin Deep, and insight from experts.