4 Byrdie Editors Tried Glossier's Lash Slick Mascara—Here's What Happened

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Glossier Lash Slick

Glossier Lash Slick

Byrdie / Avery Stone

What We Like
  • Defines and lengthens lashes

  • Nourishing ingredients

  • Doesn't clump

  • Lashes feel lightweight and soft, never stiff

What We Don't Like
  • Results were subtle

  • One reviewer experienced flaking after hours of wear

Overall, our editors thought that Glossier's Lash Slick mascara was a standout option if your goal is a more natural, low-key look.


Glossier Lash Slick

Glossier Lash Slick

Byrdie / Avery Stone

Our editors put Glossier's Lash Slick to the test after receiving complimentary samples from the brand. Keep reading for our full product review.

In the world of no-makeup-makeup, Glossier pretty much reigns supreme. So when the brand launched Lash Slick, its first-ever mascara, it was a big deal, to say the least. The innovative formula—which took the brand 18 months and 248 iterations to perfect—uses Japanese technology to add tiny curved fibers to the tips of your lashes (think: baby lash extensions), while keeping lashes soft and nourished. The end result is a natural, your-lashes-but-better look, and beauty lovers, editors, and celebrities alike (Michelle Obama wore it on Inauguration Day this year—enough said) are fans.

To see how Lash Slick looked and felt on different lash types, we had four Byrdie editors try the formula themselves. Read on for their honest reviews.

Glossier Lash Slick

Uses: Conditioning and lengthening the appearance of eyelashes

Best for: Eyelashes

Active Ingredients: Vitamin B5, Biotinyl Tripeptide-1

Potential Allergens: Beeswax

Cruelty-Free? Yes

Price: $16

About the Brand: Glossier is known for its millennial- and Gen Z-friendly skincare and cosmetic products that give you a natural, no-makeup-makeup look.

Ingredients: Nourishing and lengthening

Let's get something out of the way: Glossier's Lash Slick formula isn't designed to pump up the volume on your lashes. In reality, it's more similar to mini-lash extensions, thanks to the aforementioned Japanese fiber technology, which deposits one- and two-millimeter-long curved fibers onto the tips of your lashes for a lifted and lengthened look. Also notable on the ingredient list are provitamin B5 and biotinyl tripeptide-1, which help keep your lashes nourished and soft, and natural shine polymers, which amp up the finish on the black pigments in the formula.

It's also worth noting that Lash Sick is water-resistant (but not waterproof!), as well as cruelty-free, dermatologist- and ophthalmologist-tested, fragrance-free, and suitable for those who wear contact lenses.

Glossier Lash Slick

Byrdie / Avery Stone

However, although this product is safe for sensitive eyes, it may not be considered clean by Byrdie's standards because it contains PEGs: "The process of making PEGs involves ethoxylation, which produces 1,4-dioxane as a byproduct," the pledge reads. "According to the National Toxicology Program, '1,4-dioxane is reasonably anticipated to be a human carcinogen.' We consider this a safe ingredient to include if the company can confirm the contaminants have been stripped."

When Byrdie reached out to Glossier to inquire about if potential contaminants have been stripped, a brand representative said the following: "We aren't able to confirm whether or not the contaminants have been stripped.... [but] the ingredients have been verified by the EWG as being of low concern, so it should fulfill Byrdie's requirements for PEGs, or at least provide more information on their safety." We'll give this one a maybe!

Review 1: Leah Wyar, SVP/GM

Glossier Lash Slick

Leah Wyar / Design by Cristina Cianci

About My Lashes

My lashes are very fine and nearly invisible without mascara. I usually go for an extra black, super volumizing formula so that my lashes look really long, thick, and dark.

The Application: The wand is rubbery, very flexible, and is thinner at the tip than the base—all things that let you grip, coat, and separate every last lash. Weirdly, however, I did end up poking my eyeball a few times trying to get too close to the root while aggressively rubbing it back and forth to build volume.

I had to really work it through and apply it again and again to get much volume or thickness.

The Results: It was great at tinting and lengthening them. I had to really work it through and apply it again and again to get much volume or thickness. There was no clumping. I did have a bit of flaking at the end of the day when I was itching or rubbing my eyes. I'd use it again, but really on off-duty time-frames, or over the weekend. Personally, it's just not enough lash for my wimpy lashes.

Review 2: Olivia Hancock, associate editor

Glossier Lash Slick

Olivia Hancock / Design by Cristina Cianci

About My Lashes

My lashes have always been an average length and thickness but don't really hold a curl. When I'm on the hunt for a new mascara, I'm searching for one that will add definition, volume, and length to my lashes so they're more noticeable IRL and when I take photos.

The Application: The design of the Lash Slick wand and its bristles makes it easy to get to the root of your lashes and rake the mascara through evenly. The beautiful pink tube that houses the mascara is also well-made as it prevents any excess product from clinging to the wand and creating clumps on your lashes.

It defined my lashes well and gave them a slight lift.

The Results: For me, all of the results were subtle. And honestly, that was what I anticipated since Glossier markets it this a mascara that gives you a "baby extensions effect." It defined my lashes well and gave them a slight lift. There was no smudging and flaking, as promised. But, the volumizing and lengthening effects that I typically like my mascara to provide were missing. After using it, I can tell that this is one of those mascaras that are more suited for when I'm doing an everyday makeup look and want to slightly enhance my lashes.

Review 3: Avery Stone, senior commerce editor

Glossier Lash Slick

Avery Stone / Design by Cristina Cianci

About My Lashes

My lashes are fairly average in terms of thickness and length but are blonde at the tips. However, over the last three months, I've been testing Lilash's Lash Growth Serum, so they're definitely longer than normal, though still fairly light. I usually opt for a mascara that lengthens, volumizes, and doesn't flake (a serious pet peeve of mine, especially since I wear contact lenses).

The Application: Honestly, of all the mascaras I've tried, this was one of the easiest to apply. I credit Glossier's tapered comb brush, which coated each of my lashes from root to tip without any clumping at all. Seriously—I didn't even need to wipe the wand off on the top of the tube.

Glossier's tapered comb brush coated each of my lashes from root to tip without any clumping at all.

The Results: This mascara is advertised as a lengthening mascara, and for me, it totally fit that bill. While it does leave something to be desired in terms of volume, I absolutely love it for a natural, laid-back look.

Review 4: Eden Stuart, associate editor

Glossier Lash Slick Mascara

Eden Stuart / Design by Cristina Cianci

About My Lashes

My mascara has two jobs to perform: Don't look clumpy, and don't flake. My lashes are decently long and curled—let's say "above average"—but I do still like being assisted by a great mascara.

The Application: I love the wand for this product! Great for picking up the product and distributing it evenly.

I'm obsessed with this product. It makes my lashes look long, with a natural curl.

The Results: I'm obsessed with this product. It makes my lashes look long, with a natural curl. I don't think there's much of a volumizing effect, but I don't mind; I like how natural the end results are—call it "my lashes, but better." As much as I firmly defend my drugstore mascaras (and I do still love them!), I think I have a new go-to.

Glossier Lash Slick Mascara

Byrdie / Avery Stone

The Value: Worth the price if you love a natural look

At $16 per 0.29-ounce tube, the price point of this mascara sits right between drugstore mascaras, many of which you can snag for around $10, and luxury mascaras, which tend to be priced upwards of $25. If you think you'd use this mascara often enough in about three months (which is the approximate amount of time you should use a tube of mascara before you toss it), you can't go wrong with this formula.

Similar Products: You've got options

Essence Lash Princess False Lash Effect Mascara ($5): A cult-favorite drugstore mascara with thousands of five-star reviews, Essence Lash Princess is another go-to of Eden's. Similar to Lash Slick, it lengthens and curls, but she also says it adds a bit more volume—perfect if you want slightly more noticeable results that still look natural. Oh, and the $5 price tag doesn't hurt, either.

Kosas The Big Clean Mascara ($26): A Team Byrdie favorite, this mascara is priced higher than Lash Slick (at $26 per 0.32-ounce tube), but is totally worth the investment for its clump-free formula and easy-to-use ergonomic wand. Plus, if you want the option to add depth and volume, it's very buildable, and you can rest assured knowing that it's clean by both Byrdie and Sephora standards.

Final Verdict

According to our editors, if you love your mascara to have a thickening, volumizing effect, then this probably isn't the one for you. But if a natural, off-duty look is what you're after, instead, you can't go wrong with Lash Slick. Its innovative formula, clump-free applicator, and chic packaging are all major wins in our book.


  • Product Name Lash Slick
  • Product Brand Glossier
  • Price $16.00
  • Weight 0.29 oz.
  • Ingredients Aqua/Water/Eau, Acrylates Copolymer, Alcohol, Cera Alba/Beeswax/Cire d'abeille, PEG-15 Glyceryl Stearate, Cera Carnauba/Copernicia Cerifera (Carnauba) Wax/Cire de Carnauba, Butylene Glycol, Kaolin, Pullulan, Behenyl Alcohol, Bentonite, Rayon, Alcohol Denat., Dimethicone, Stearic Acid, Sucrose Distearate, VP/VA Copolymer, Nylon-6, Aminomethyl Propanol, Glycerin, Tocopherol, Silica, Panthenol, Biotinoyl Tripeptide-1, Sodium Dehydroacetate, Phenoxyethanol. May Contain/Peut Contenir (±): CI 77491, CI 77492, CI 77499 (Iron Oxides), CI 77266 (Black 2)

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