Merit Great Skin Serum Review: My Honest Take On The Glowy Prep Step

I’m always chasing that “my skin but better” look, and makeup is only half the battle. The real secret is the prep. I’ve tried countless glowy primers and hydrating serums, but Merit’s Great Skin Instant Glow Serum is in a league of its own.

It’s the bi-phase, skin-loving cocktail my face was missing. If you’re looking for a one-step product to instantly hydrate, plump, and give you a radiant canvas that looks amazing under makeup or on its own, you absolutely need to try this.

My Experience With Merit Great Skin Serum

My social media feeds are a constant barrage of “holy grail” products that promise to change my life. Most of them are overhyped and end up in my skincare graveyard. But Merit’s Great Skin Serum kept showing up, and it was different. It wasn’t just the viral hype; it was the aesthetic. The bottle is this impossibly chic, minimalist, dual-phase liquid—a clear “water” phase and a golden “oil” phase—that you have to shake. It looked like a modern-day potion. As a total sucker for “clean” beauty and the minimalist vibe that Merit champions, I was intrigued.

My skin profile is the classic, frustrating combination type.

My cheeks and under-eyes are perpetually dry and can get patchy, while my T-zone (forehead, nose, chin) gets oily by 3 PM. This makes makeup a challenge.

Most “glowy” primers just make my T-zone look like a greaseball. Most “mattifying” primers make my cheeks look chalky and dry.

I’ve spent years searching for a product that could hydrate my dry patches without overwhelming my oily spots.

I wanted a skincare product that functioned like a makeup primer, not the other way around.

I finally caved and bought it. The unboxing experience itself felt luxurious. The bottle is made of heavy, frosted glass and has a satisfying weight in the hand. It looks and feels expensive. The pump is smart, and the instructions are simple: “Shake well.” This is genuinely the most satisfying part of the ritual. Watching the two distinct layers collide and transform into a uniform, milky, pale-yellow emulsion feels like I’m “activating” the serum.

I pumped two drops onto my fingertips. The texture is what really shocked me. It’s completely unique. It’s not a sticky gel. It’s not a heavy, slick oil. It feels like a… silky water? It’s a true “serum-oil” that glides across the skin with zero friction. It’s not tacky, it’s not greasy, and it’s not sticky. This was a massive win. I cannot stand feeling a heavy, siliconey, or sticky layer on my face.

And the “Instant Glow” name is not an exaggeration. Within about 30 seconds of patting it in, my skin looked… different. It wasn’t glittery. It wasn’t shimmery. It just looked healthy. It was a dewy, plump, post-facial kind of radiance. It looked like my skin, but on its absolute best day, after eight hours of sleep and a gallon of water. It soaked in almost completely, leaving behind this plump, soft, radiant finish. My dry patches felt instantly soothed and looked less crepey.

But the real test, for me, was always going to be makeup. I let the serum sink in for about 60 seconds (it absorbs incredibly fast) and then went in with my go-to foundation, Merit’s Minimalist stick. The difference was immediate and profound. My foundation didn’t just sit on top of my skin; it melted into it. It blended effortlessly, without pilling, separating, or clinging to a single dry patch. It just made my foundation look like a second, perfected version of my own skin.

I’ve been using this serum every single morning for over six weeks now, and it has gone from a “like” to a “non-negotiable love.” The long-term effects are just as good as the instant ones. My bare skin genuinely feels softer, more supple, and more hydrated, even on days I forget to use it. The Niacinamide in the formula has visibly helped to even out my skin tone and calm some of my persistent redness. It has become the essential bridge between my morning skincare and my makeup, and I honestly get a little panicky when I see the liquid level starting to go down.

Read More: My Thoughts On La Roche-Posay Hyalu B5 Serum

Pros Of Merit Great Skin Serum

• The “Instant Glow” Is Authentic, Not Artificial: This is the most important pro for me, and it’s what sets this serum apart. In a market flooded with “glow” products, most are just liquid highlighters masquerading as skincare, packed with fine mica, shimmer, or pearlescent particles. Merit Great Skin has none of that. The “glow” it delivers is a genuine, lit-from-within sheen. It’s the visual result of the bi-phase formula, which contains a 58% water-phase and a 42% oil-phase. When you shake it, they create a temporary emulsion that coats your skin in a micro-fine layer of hydrating humectants and nourishing, lightweight lipids. It makes your skin look bouncy, plump, and healthy, as if you are glowing from the inside. It’s the perfect “glass skin” effect without the ten complicated steps. I wear it on its own all the time on “no-makeup” days, and I just look refreshed and alive.
• A True Skincare-Makeup Hybrid Masterpiece: This product is the perfect example of a hybrid. It doesn’t just prime your skin; it feeds it. The ingredient deck is a powerhouse of skincare all-stars. You have Niacinamide (Vitamin B3), which is a brilliant multitasker for brightening skin tone, visibly refining the look of pores, and strengthening the skin’s barrier. Then you have four different types of Hyaluronic Acid, which provide multi-level hydration, pulling moisture into the skin to give it that instant plump, bouncy feel. It also includes Cacao Seed Extract, which is rich in antioxidants to help protect your skin from free-radical damage, and Japanese Goldthread Root, a known anti-inflammatory to soothe and calm the skin. I feel like I’m applying a high-end treatment serum. But at the same time, it functions as the most elegant makeup primer I’ve ever tried. It creates a smooth, hydrated canvas that grips my foundation and concealer, preventing them from caking, creasing, or settling into fine lines.
• Phenomenal Texture And Rapid Absorption: The texture of this serum is a masterclass in cosmetic formulation. Because it’s a bi-phase, it’s incredibly lightweight and thin, feeling almost like a hydrating toner when you first pump it out. But as you pat it into the skin, you can feel the cushion and nourishment from the oil phase. The best part is the absorption. It sinks into the skin in under a minute. There is absolutely zero greasy, oily, sticky, or tacky residue left behind. My skin just feels soft, smooth, and supple. This is a game-changer for me, as I loathe the feeling of heavy, occlusive layers on my face. It doesn’t have that slick, “plastic” feel of a silicone primer, nor does it have the heavy, sitting-on-top feeling of a traditional face oil. It just feels like perfected skin.
• Beautiful, Functional, And Thoughtful Packaging: I’m a sucker for good packaging, and Merit’s entire line is an A+. The Great Skin serum comes in a beautiful, heavy, frosted glass bottle that looks and feels substantial. It’s minimalist and chic, and I love having it on my vanity. But the design isn’t just for looks; it’s highly functional. The pump mechanism is fantastic. It dispenses a controlled, small amount of product, so I never feel like I’m being wasteful. Two pumps are perfect for my entire face and neck. The bi-phase nature itself is a smart design. It’s a constant, visual reminder that you are getting both water-soluble ingredients (like Hyaluronic Acid and Niacinamide) and oil-soluble ingredients (barrier-supporting lipids) fresh with every single application. It’s aesthetically pleasing and practical.

Cons Of Merit Great Skin Serum

• Cost Per Ounce: This is a luxury product, and it has a luxury price tag. At $38 for 1.7 oz (50ml), it’s a definite investment. It’s not the most expensive serum at Sephora, but it’s certainly not a budget-friendly find. When I first started using it, I was a little too enthusiastic with my pumps (using two to three every morning), and I noticed the liquid level dropping at an alarming rate. It made me a bit nervous about the cost of repurchasing. If you’re a student or on a tight budget, this is a “splurge” item.
• Value Proposition: You are paying for the clean-at-Sephora formulation, the high-quality ingredients, the chic branding, and the unique hybrid function. Because it’s called a “serum,” my brain sometimes wants it to be a high-potency “fix-it” product, like a powerful retinol or a 20% Vitamin C. This isn’t that. It’s a hydrating, plumping, and priming serum. If you’re looking for a single product to tackle severe hyperpigmentation or deep-set wrinkles, this isn’t the one. You have to understand its job: it’s a “glow prep” step. For me, it’s worth it because it replaces my hydrating serum and my primer, but that value calculation is personal.
• Earthy And Specific: This product is proudly fragrance-free, which is a massive pro for my sensitive skin. However, “fragrance-free” does not mean “scent-free.” This serum has a distinct smell that comes directly from its raw ingredients. To my nose, it’s a very natural, slightly earthy, and almost “plant-like” or “herbal” smell. I don’t mind it one bit; in fact, I’ve come to associate it with “clean” skincare. Plus, it dissipates in about 10 seconds, literally. But I have seen other people describe it as “musty,” “like old herbs,” or just “a bit weird.” If you are extremely sensitive to any scent at all, even natural ones, this is something to be aware of. It does not smell like a perfumed, floral, or fruity cosmetic product.
• Shaking Is A Non-Negotiable Step: This is a minor con, but it’s a real one for me on a rushed morning. You must shake this bottle vigorously every single time you use it. I’m talking a good 5-second, energetic shake. If you’re half-asleep, in a hurry, and you forget, the application is all wrong. You’ll get a pump of just the watery phase (which feels thin and not nourishing) or just the oily phase (which feels greasy and sits on the skin). It’s an extra step in your routine that you have to be mindful of. It’s not a “mindless” product you can just grab, pump, and slap on.

Tips For Merit Great Skin Serum

• The Perfect Application Technique
  • Shake It Like You Mean It: My first and most important tip is to respect the bi-phase formula. You must shake the bottle vigorously for at least 3-5 seconds before every single use. You’re looking for the two layers to be completely combined into a uniform, milky, pale-yellow emulsion. This is the only way to ensure you get the perfect ratio of the 58% water phase and 42% oil phase in every pump. This balanced mixture is the entire secret to the product’s unique texture and glow.
  • Warm It Up, Press It In: I’ve found that I get the best absorption and the most seamless, “melted” look when I use my hands. I dispense one to two pumps into my clean palms, rub my hands together quickly for just a second to warm up the serum, and then press and pat it into my face and neck. I avoid rubbing or smearing it around like a traditional lotion. The pressing motion seems to help it absorb more evenly and deeply, giving a more seamless finish, especially on my dry patches.
  • Give It A Minute To Set: This serum is a speed demon at absorbing, but it’s not instantaneous. I always give it a full 60 seconds to sink in and “set” on my skin before I go in with any makeup, whether it’s concealer, foundation, or even just a tinted moisturizer. This brief waiting period is crucial. It allows the serum to form its hydrated, glowy canvas and ensures that your base products won’t pill or streak.
  • Don’t Overdo It: My first instinct was to use three pumps because it felt so good. That was a mistake. It just made my skin feel too slippery, and my makeup didn’t grip as well. For my combination skin, one and a half to two pumps is the absolute sweet spot. If you have very oily skin, one pump might be all you need. Start with less; you can always add more.
• How To Layer It In Your Routine
  • The “Serum-Moisturizer” Step: The most common question is: “Where does this go?” I’ve had the most success treating it as a lightweight moisturizer or a final “sealing” serum. My ideal morning routine is: Cleanse, Tone, (optional) a targeted, water-based serum like a Vitamin C, and then the Merit Great Skin.
  • For Dry Skin: On my extra-dry-skin days or in the dead of winter, I will apply my regular, thicker moisturizer or SPF after the Merit serum has fully absorbed. The serum acts as a hydrating base layer, and the moisturizer locks it all in.
  • For Oily Skin: If you have oily or combination skin, this product can often be your only moisturizer for the day, especially in the humid summer months. On a hot day, I’ll cleanse, tone, and then just use two pumps of Great Skin followed by my sunscreen. It provides the perfect amount of hydration from the hyaluronic acid and the barrier-supporting lipids without feeling heavy or greasy. It gives me a glow, not an oil slick.
  • The 3 PM Makeup Refresher: This is my favorite hack. Around 3 PM, when my under-eyes look dry and my makeup looks a bit flat and “makeup-y,” I’ll pump half a pump onto the back of my hand. I’ll take my ring finger, warm it up, and then gently press and tap the serum over my makeup on my cheekbones, under-eye area, and any other dry spots. It instantly revives my look, melts the makeup back into my skin, and brings back that dewy glow without breaking up my foundation. It’s a lifesaver.
• Storage And Handling
  • Keep It Out Of Direct Sunlight: Like most high-quality skincare products, especially those with natural, active ingredients like Cacao Seed Extract, you should store your bottle in a cool, dry place. The frosted glass helps protect the formula, but direct sunlight is its enemy. It can degrade the ingredients and destabilize the bi-phase formula. My bathroom cabinet or a shaded spot on my vanity is perfect.
  • Use The Cap: The bottle comes with a very nice, secure cap. I make a point to put it back on after every use. This does two things: it keeps the pump nozzle clean from dust and bathroom gunk, and it prevents any accidental dispensing if the bottle gets knocked over. It’s a small, two-second habit that keeps the product hygienic and pristine.

Comparison With Other Brands

• Versus Traditional Silicone Primers
  • The Feel And Finish: When I put Merit Great Skin up against a classic silicone-based primer like the Smashbox Photo Finish or the Benefit POREfessional, it’s a completely different universe. Those primers are heavy on silicones (like dimethicone), which create a very slick, thick, almost “spackle-like” layer on the skin. They work by filling in your pores and fine lines. Merit Great Skin doesn’t do that. It doesn’t “fill” anything. It hydrates and plumps the skin around the pores, making them appear smaller and less obvious. It feels like nourishing skincare, whereas silicone primers feel like a temporary, synthetic layer. The finish is “dewy and plump,” not “matte and flat.”
  • The Long-Term Benefits: A silicone primer is, for me, a purely cosmetic fix. It helps my makeup look good for an event, but when I wash it off, my skin is exactly as it was before, and sometimes even a bit congested from being “filled in” all day. With Merit, I’m applying Niacinamide, Hyaluronic Acid, and antioxidants every single morning. After weeks of consistent use, my bare skin looks visibly better, brighter, and more hydrated. It’s a primer that is also a long-term treatment, which gives it infinitely more value in my routine.
• Versus Other “Glow” Serums
  • The Glow Source And Texture: My main comparison here is the viral Glow Recipe Watermelon Glow Niacinamide Dew Drops. I’ve used and liked the Glow Recipe serum, but it’s a totally different product. It’s a pink, gel-based serum that creates a very “wet” glow. On my combination skin, it can feel a bit tacky or sticky if I use even a drop too much, and it takes longer to dry down. Merit’s bi-phase formula absorbs completely, leaving a “sheen” or “radiance” rather than a “wet” look, and it feels much more lightweight. The Glow Recipe also has a very strong, sweet watermelon candy fragrance, which I got tired of. Merit is fragrance-free, which my sensitive skin prefers.
  • The Bi-Phase Competitors: The closest product in formulation is something like the Kora Organics Noni Glow Face Oil or the Youth to the People Superberry Hydrate + Glow Dream Oil. Both of these are also bi-phase oil/serums. However, those products are true face oils. They are much heavier, richer, and more nourishing. I’ve used the Kora oil, and for me, it’s a nighttime treatment to lock everything in. It’s too heavy to wear under makeup. Merit Great Skin is specifically formulated to be the opposite: it’s an ultra-light, fast-absorbing bi-phase designed for daytime and as a primer. It’s the “day” version of those heavier “night” oils.
• Versus Hydrating Essences
  • The Emollient Factor: For a long time, I used a hydrating essence, like the COSRX Snail Mucin Essence, as my main “prep” step for hydration. An essence like that is a pure humectant. It’s designed to pull water into the skin, making it plump and damp, which is great. But it lacks an emollient (oil) phase. This means I always had to follow it with a moisturizer to seal that hydration in. Merit Great Skin has both phases. It has the humectant “water” phase (with Hyaluronic Acid) and the emollient “oil” phase. This means it doesn’t just add hydration; it seals it in at the same time. It gives my skin that soft, conditioned, and protected feeling that a simple essence can’t provide on its own.

Also Read: My Thoughts On La Roche Posay Mela B3 Dark Spot Serum

Frequently Asked Questions (FAQ)

Conclusion

After weeks of daily use, Merit’s Great Skin Serum has earned its permanent, holy-grail spot on my vanity. It’s not just makeup, and it’s not just skincare—it’s the perfect, glow-giving hybrid of both. It’s the one product that instantly makes my skin look plump, healthy, and radiant. If you’re tired of cakey makeup, dull-looking skin, and primers that feel like plastic, you need this bottle in your life. It’s an investment, but for me, it’s one I’ll be making again and again.