COSRX

The Niacinamide 15 Serum

16 Reviews

• 순수한거미원숭이877

  Jun 27, 2025 (UTC)
  Oily SkinAcne Skin
  Review under verification

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  An ampoule that's perfect for oily skin to control excess sebum! Despite its high niacinamide content, it absorbs wonderfully! When applied in the right amount, it sinks in quickly. It seems to smooth out dead skin cells, leaving your skin texture looking great the next day.

  Cons

  Due to its high niacinamide concentration, it might pill if applied right before makeup. However, if your skin is well-prepped and in top condition, it can actually create a nice, matte finish for your makeup.

  Tip

  Even if you have oily skin, it can still get dehydrated, so it's a good idea to apply a light layer of a hydrating serum as well.

---

• 봉봉커피

  May 1, 2025 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I initially applied this product on my bare face in the morning, but noticed some pilling when applying makeup. Now I use it alternately with my vitamin C product in the evenings. I've been using it for two months, though not consistently. I apply it on mornings when I'm not wearing makeup or using vitamin C products. 1. While the effects aren't immediate, I notice my skin looks a bit brighter the day after using this product. This is likely due to the high 15% concentration of niacinamide, which seems to have a positive impact on the skin. With consistent use, you'll definitely notice your skin becoming more radiant. 2. The product itself is quite hydrating. While it doesn't provide long-lasting moisture like hyaluronic acid products, it's surprisingly hydrating for a niacinamide serum. Those with oily or combination skin might find this product alone sufficient without an additional cream. However, it has a slightly gel-like texture that forms a film on the skin. This film doesn't stay moist for long, so those with dry skin might notice their wrinkles and pores becoming more pronounced over time. I'd recommend pairing it with a hydrating ampoule or cream. 3. When applied, this product smooths out skin texture and doesn't emphasize dead skin cells. 4. The ingredients are gentle and non-irritating. I experienced no blemishes, excess oil production, tingling, or redness.

  Cons

  1. The niacinamide in this product has a sticky texture that can cause makeup to pill, making skin look a bit messy. While the pilling isn't severe, it's noticeable around the cheekbones and eye area, which can be inconvenient as it requires touch-ups. 2. Even though it's not for daily use, the price is quite high for the small amount you get. I find myself waiting for sales to purchase it. 3. The product is almost fragrance-free, but there's a slight scent reminiscent of glue mixed with saliva. However, if you're not sensitive to smells, it's barely noticeable. I actually prefer this to artificial fragrances that can cause headaches. 4. I'm not sure how many bottles it takes to see results, but I'm still on my first bottle and honestly can't say I've noticed any improvement in blemishes, blemish marks, or pores. 5. The dropper is quite short, so one full dropper isn't enough to cover my entire face (maybe I have a big face?). It's a bit inconvenient having to use the dropper twice for each application.

  Tip

  For those who need to apply this product in the morning, I recommend using a small amount to prevent makeup pilling. After application, pat it in well and allow some time before applying makeup.

  • 
  • 
  • 
  • 
  • 
  • 

---

• 비인짜앙

  Mar 22, 2025 (UTC)
  Combination SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I have combination dehydrated skin prone to blemishes! My skin hasn't improved since my student days... I've been using niacinamide for quite a while, but its characteristic stickiness was so intense that I found myself avoiding it. As I used it less and less, my skin suddenly flared up, making me seriously consider seeking help from a dermatologist. With moving and changing jobs, my skin kept acting up as my overall condition declined, so I completely revamped my skincare routine! This product, which I purchased during that overhaul, absorbs so quickly that at first I wondered if I'd even applied it. It leaves a slightly oily residue. Due to the nature of niacinamide, it can sting quite a bit on sensitive areas or open wounds. However, with consistent use, it helps regulate sebum production and reduces texture! Even though the price makes me wince a bit, it's become a repurchase-worthy magic potion. This broke girl is... Following this routine: toner > niacinamide > bakuchiol serum > mist > cream, I've noticed my skin improving significantly, and even old scars seem to be fading bit by bit.

  Cons

  For first-time users, you might experience some deep dryness if you only use this product! It would be great to use it with hydrating toners and emulsions or creams before and after, but I'd recommend layering a cream toner containing ceramides 2-3 times, then finishing with an ampoule, emulsion, or cream. There is a slight oily residue left behind! If you're worried about your makeup pilling, apply an appropriate amount and gently blot with oil-absorbing sheets.

---

• opklnm76

  Feb 15, 2025 (UTC)
  Oily Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  The consistency is just right - not too thin or oily, making it pleasant to apply. It controls sebum well, and with consistent use, I've noticed a significant reduction in blemishes.

  Cons

  If you apply too much, it can pill a bit. Other than that, I don't have any particular complaints.

---

• 힘이센아빠상어

  Dec 5, 2024 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I bought this product out of curiosity since it's consistently ranked at the top. I only used it at night because I need to apply sunscreen diligently during the day. The short-term effects are impressive! While it didn't tighten my pores as much, I noticed a significant improvement in evening out my skin tone.

  Cons

  Exfoliation is an absolute must! If you have dead skin cells, it actually causes the product to pill.

  • 

---

• 이연째

  Jul 8, 2024 (UTC)
  Dry SkinSensitive Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  With a whopping 15% niacinamide content, this is a true blemish solution serum that tackles everything from the root cause to the aftermath of breakouts. As summer approached and the weather got warmer, I was on the hunt for a serum to control excess oil. This one absorbs well, leaving skin hydrated without any stickiness, and finishes with a soft, matte feel that really keeps oiliness in check. It effectively regulates overactive sebum production, making it an especially great summer serum recommendation for those with combination dehydrated skin!

  Cons

  However, I'm not sure if it's just me, but I noticed some pilling, almost like dead skin cells rolling off. This happened even when I didn't apply a heavy layer of toner underneath.

  • 
  • 
  • 

---

• 맨듇

  Jun 2, 2024 (UTC)
  Dry SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I was worried about potential irritation due to the high concentration, but when used on unbroken skin, I didn't feel any discomfort! I accidentally touched a small wound on my face and that area stung intensely, so I immediately wiped it off, applied a patch, and reapplied. After that, there was no stinging sensation! I'm not sure about the brightening effects yet, but it seems to have helped with pore management.

  Cons

  It seemed to pill slightly before makeup application, so I only used it before bed.

  Tip

  Use at night!

---

• 편안한물까치804823

  Jan 28, 2024 (UTC)
  Dry SkinSensitive Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  The price is so friendly that it's great for using without any financial burden

  Cons

  After application, there's a pilling effect like dead skin cells. The texture doesn't match the tip. It's too runny, dripping down and often falling off the face

---

• Rrnv

  Jan 13, 2024 (UTC)
  Combination SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  It absorbs well without feeling sticky. After a while, I noticed it helped control some excess oil.

  Cons

  It often pills when applying, like dead skin. As you spread it, you might notice residue on your hands and face.

---

• 골골97

  Sep 20, 2023 (UTC)
  Oily SkinSensitive SkinAcne Skin

  Review under verification

  The content is currently being reviewed by the Hwahae operations team, and the verification will be completed by the next business day (excluding weekends and holidays) from the date the review was written.

  OK

  Reviewed by The Hwahae Testers

  This review was written by The Hwahae Testers who received the product for free and evaluated it with a sense of representing Hwahae. The review is completely unbiased and honest, with no guidelines or restrictions. Reviews by The Hwahae Testers undergo the same strict verification process as regular reviews, and if they don't meet our standards, revisions will be requested.

  OK
  Pros

  I'm writing this review after using up the entire bottle! It was my first time trying a product with niacinamide, so I was worried about potential irritation, but there was absolutely none. I noticed a significant reduction in sebum production, and I felt my skin texture improving compared to before.

  Cons

  There's a bit of pilling, unfortunately. I thought it might be due to dead skin cells, so I exfoliated before applying, but it still pills...

  Tip

  Try consistently applying your skincare in this order: niacinamide serum > retinol serum > panthenol cream!!! You'll feel your skin becoming smoother and firmer!