My New Favorite Vitamin C Serum.

Biossance Squalane and Vitamin C Dark Spot Serum Review

Sponsored by Biossance and Shopstyle.

I could not be more excited to team up with Biossance again. You may remember that I worked with them back in November to talk about my favorite products. Well today, I am back again, to talk about a NEW product from them: their Squalane and Vitamin C Dark Spot Serum! I think that you guys are going to really love this one as I am always getting asked for Vitamin C serum recommendations but I hadn’t consistently used a daytime Vitamin C serum until more recently (I have been testing this one out since early December, so I’ve had a lot of time to play with it.)

 My New Favorite Vitamin C Serum

First of all, Biossance is hands down, one of my favorite skincare brands. I love that they make formulas that are clean and safe, but also highly effective. Their products are truly transformational, board certified dermatologist approved, with high concentrations of active ingredients. I also really love their commitment to science and the environment. And maybe most notably, what they’ve done for the beauty industry by developing a squalane oil (the core of all their products) that is derived from sugar cane (not sharks!). Squalane is the key ingredient all of their products. It hydrates deeply, which you really need when you are using actives like Vitamin C, phyto-retinol, and lactic acid. I’m also a giant fan of their glycolic acid mask. More recently, I have absolutely loved their squalane and copper peptide serum – the perfect shot of long-lasting hydration. It plumps up the skin (reducing the appearance of fine lines) and is actually great to apply before this face serum… they work really well together, especially if you have dry skin. Truly, I could go on and on about this brand all day!

Biossance Squalane and Vitamin C Dark Spot Serum Review

Biossance has two amazing vitamin C products. There’s the original Squalane and Vitamin C Rose Oil, and then there is the brand new Squalane + Vitamin C Dark Spot Serum.

Biossance Squalane and Vitamin C Dark Spot Serum Review

But first: why Vitamin C?

Vitamin C is a POTENT antioxidant and an important step in any anti aging skincare routine:  it brightens up the skin while also supporting collagen production. (And more collagen is the thing we all want as we get older – it plumps up those fine lines!!!) Biossance uses a unique water soluble Vitamin C that remains stable in the bottle and won’t irritate your skin.

Biossance Squalane and Vitamin C Dark Spot Serum Review

Biossance Squalane and Vitamin C Dark Spot Serum

This formula contains 10% of Biossance’s unique Vitamin C complex. In addition to that, it contains Biossance’s sugarcane derived Squalane to keep skin hydrated and soft, and White Shitake Mushroom Extract which helps to fade dark spots and discoloration.

This serum will give you glowing skin immediately, and over time it helps to fade existing dark marks and prevent new ones from happening. It is safe for sensitive skin types, and if you have acne prone skin it can even help to fade the look of acne scars. The opaque bottle protects the formula from exposure to light.

How to use it:

This is a MORNING treatment! I mostly do my actives at night but love a good day serum. A quick refresher on morning product order: cleanse (and tone if you tone), apply eye cream. Then apply your serum (this!), moisturizer, oil (if you need one, I tend to use oils at night) and SPF.

My Take:

I love this product. I do not have a lot of dark spots or discoloration but my skin definitely can get uneven and patchy. This evens my skin tone out dramatically. I love how much brighter my skin looks after using this every morning for 6 weeks. I also love that it is not sticky. This is the first vitamin C serum I’ve tried that is not sticky, which is big! Even the famous Skinceuticals C E Ferulic and Drunk Elephant vitamin C have felt sticky on my face which is a giant no for me.

Biossance Squalane and Vitamin C Dark Spot Serum Review

You might already be familiar with Biossance’s Squalane and Vitamin C rose oil. This is a great way to add more of those Vitamin C brightening benefits into your routine but it is an oil and not a serum, so this would be the last step of your routine. You could use it concurrently with the serum. It contains oil-soluble, shelf-stable vitamin C, though in much lower levels than the Vitamin C Dark spot serum.

Biossance serum comparison

I thought this chart was really, really helpful to understand how the new treatment compares to the rose oil as well as the other Biossance serums. The new serum is going to be your key weapon against discoloration, uneven skin tone, and dullness… whereas the oil helps with hydration and RADIANCE!

Biossance serum review how to use Biossance serums best Biossance products

While I have you I couldn’t help but share a few more Biossance favs (I LOVE THIS BRAND SO MUCH).

Squalane and Lactic Acid Resurfacing Night Serum

This is my holy grail for texture issues. I use this a few times a week for smooth, smooth skin. I have written about this extensively (this post is a good one to reference!) but just trust me: it’s the BEST.

Squalane and Phyto-retinol Serum

I’ve featured this one a bunch, too! If you are looking for a plant-based retinol alternative, you’re going to love this. This is what you want to use for fine lines and wrinkles… and plumpness!

Squalane and Glycolic Renewal Mask

I love this mask for when I want glowy smooth skin but don’t have the time or patience to do an overnight treatment. Throw this on for 15 minutes (followed by your favorite moisturizer and maybe a little of the Vitamin C Rose Oil) to GLOW.

Biossance product review
Biossance Squalane and Vitamin C Dark Spot Serum Review

Photography by Allie Provost


Leave a Comment

Leave a Comment


  1. I’m currently using The Ordinary’s vitamin c serum, would be interesting to try out Biossance’s products after this! ❤️✨

    Charmaine Ng | Architecture & Lifestyle Blog

    1.26.21 Reply
  2. Abby:

    Thanks for this recommendation! I’ve been on the hunt for a new serum. Do you think the serum would be as effective without the oil though?

    1.26.21 Reply
    • Oh yeah absolutely. The oil would just be a booster, if you needed extra moisture etc. I don’t typically use them together as I use this during the day and I don’t do oils during the day. I love the oil for night.

      1.26.21 Reply
  3. Katy:

    Thanks for your thoughtful review and love the chart! I am curious— are you a permanent vitamin C convert now?!

    1.26.21 Reply
  4. This post is SO HELPFUL! I got the Vitamin C Rose Oil months ago and was so confused how to use it. I always used your advice and applied it after my moisturizer, but everything I knew about Vitamin C had me thinking it should be sitting closer to your skin. I ended up buying the Farmacy Vitamin C because the oil confused me. The chart included in this post is a game changer and I appreciate your breakdown of the products. Yet again, you’ve saved my skin!

    1.26.21 Reply
    • Aw I’m so glad to hear that!!! I had questions too so I asked the brand. The concentration of vitamin C in the oil is pretty low so it’s not a true vitamin c serum, more like an oil with added benefits.

      1.26.21 Reply
  5. Kim Burkhardt:

    You have turned me onto Biossance products – their lactic acid serum has transformed my skin (my husband even commented on it without me mentioning it) after just one week of use. At week four I am SO confident and typically have a lot of texture issues. I actually just skipped a facial (!!!!) I just started using the vitamin C serum today and am hopeful my dark spots will be gone. Your recommendations are the bomb.

    1.26.21 Reply
    • Aw thank you!!!! I am so happy to hear that. The lactic acid was my gateway into Biossance’s world and now I am hooked on all their products.

      1.26.21 Reply
  6. Rebecca:

    Love the review. Noticed that their squalane and marine algae eye cream didn’t make your other Biossance faves list! I’m looking for a hydrating eye cream. Do you still like theirs, or are the others you prefer (similar price point)? thanks!!

    1.26.21 Reply
    • I like the eye cream a LOT and at that price point it’s probably the best one out there but right now my go-to eye cream is Neocutis. I’ve reviewed the eye cream several times here (if you use the search!) and everything I say about it still rings true.

      1.26.21 Reply
  7. Maria:

    Super helpful! I am going to order. Question: how does this fit with a hyaluronic acid product? Can I use that at night and this Vitamin C serum in the morning?

    1.26.21 Reply
  8. Mollye:

    Grace, thanks for the great review. I’ve been a CE Feurlic user for years but stopped using it when I switched to Bader. Can you remind me what your daytime moisturizer is with this product?
    Thank you!

    1.26.21 Reply
  9. Nora:

    So helpful! I tried the rose oil but it was too oily for my (oily) skin, will definitely try this one. I love the lactic acid as well thanks to you! I did find the bottle design of the phyto-retinol frustrating, it felt like a lot was left in the bottle that couldn’t be pumped out.

    1.27.21 Reply
    • Oh no, that is a bummer to hear! I feel like packaging is the only thing Biossance needs to work on. And I know it’s from a good place of wanting to be sustainable (and by using less packaging the product can be less expensive) but I agree!

      This one would be great for oily skin though!

      1.27.21 Reply
  10. Heather:

    Thanks for the review! I have been looking for a slightly cheaper alternative to my Skinceuticals CE Ferulic. Have you tried that/able to compare?

    Also just a vent– I know you are not in charge of Biossance’s marketing, but I was briefly impressed by this product’s rating on Sephora until I realized 95% of the reviews were from people who had gotten free product. That always leaves a bad taste in my mouth.

    1.27.21 Reply
  11. Crissy:

    Hi, Grace! Thanks for this review. I recently bought Kiehl’s Powerful-Strength Line-Reducing Concentrate (with Vitamin C). How does Biossance compare? Thanks so much 🙂

    1.27.21 Reply
    • Hey Crissy! Great question. They’re totally different products! I use this one in the morning to BRIGHTEN and even out my skin tone. The Kiehl’s is an evening treatment for fine lines and texture.

      1.27.21 Reply
  12. AK:

    Hi Grace, I’m a huge Biossance convert because of you and have just ordered this new serum. I know you don’t suffer from acne, but for those of us who do have the occasional breakout if we don’t use an acne treatment, where should that go in the order of things? I put it after eye cream but before serum as i want the treatment to soak in and do its job…what say you?

    2.1.21 Reply
  13. Katie Stein:

    Hi Grace! Can you use the lactic acid and Retin A combined at night since they both seem like night time products and use the Vitamin C in the morning?

    2.12.21 Reply
    • I would not use lactic acid and retin A together, I’d alternate nights! And then yes, Vit C in the AM. My rule is generally ONE active at a time, never mixing. But talk to your derm!

      2.12.21 Reply
  14. Lynn E:

    This may have already been asked, but how does this fit in with Bader? I usually use it by itself in the AM and use my actives at night. But, I’ve been wondering about using Vitamin c somewhere in my routine.

    2.20.21 Reply
    • Honestly, I’ve been using it under Bader (shhhhh). But to be honest my rule for Bader is just to make sure I use it at least once a day. I mix up my skincare a lot, so some days I’ll do this + the Sobel skin in the AM, and then Bader at night but other nights it’s a retinol night so I’ll do this + Bader in the morning and then my retinol at night. Hope that helps!

      2.22.21 Reply