Firm + Replenish

A must after cleansing, this serum restores your skin barrier by replenishing your natural moisturizing factor (NMF) and the essential lipids in the skin. Featuring a double dose of our patented B-SILKTM PROTEIN, which combines the power of collagen and elastin into one, it keeps your skin supple with nourishing ceramides and squalane plus elasticity building, skin firming amino acids for better skin health.

Formulated without: Fragrance, Silicones, Parabens, Mineral Oil, Petrolatum

We are: EWG Verified, Leaping Bunny Certified, Vegan

Do you cleanse daily?* You need this. Apply two to three pumps to face, neck, and décolletage after cleansing and/or exfoliating in the AM and PM. For best results, follow with your favorite Eighteen B Moisturizer.

Pro Tip: If you’re using any active treatments (retinol, vitamin c etc.) or oils, apply them before Firm + Replenish Serum so B-SILKTM PROTEIN can lock in the benefits. *If you’re not cleansing daily, we should talk. It's important to start and end the day with fresh, clean skin. Your pores will thank you (and be smaller)!

[ "Water (Aqua), Squalane, Pentylene Glycol, Silk Protein, Sodium Hyaluronate Crosspolymer (Hyaluronic Acid), Ceramide AP, Ceramide EOP, Ceramide NP, Alanine, Arginine, Aspartic Acid, Glycine, Histidine, Isoleucine, Phenylalanine, Proline, Serine, Threonine, Valine, Cholesterol, PCA, Sodium PCA, Sodium Lactate, Phytosphingosine, Sodium Lauroyl Lactylate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Xanthan Gum, Carbomer, Polysorbate 60, Hexylene Glycol, Ethylhexylglycerin, Caprylyl Glycol, Sorbitan Isostearate, Disodium EDTA, Phenoxyethanol." ]


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Since we created B-SILK™ PROTEIN, we needed to prove that it is really as great as we think it is. In a clinical trial, based on expert grading evaluations:

After 4 weeks

After 8 weeks


Showed a reduction in the appearance of fine lines



Showed improved elasticity


+80%saw firmer, more nourished skin after 4 weeks of using Firm + Replenish Serum
Serums are treatment products that deliver concentrated doses of “active” ingredients to fix the things you want to fix (though we think you look fab)!

Serum 101:

  • Apply serums first because you want high performance actives close to the skin to work well.
  • Our serum features B-SILK™ PROTEIN to reinforce your skin’s natural barrier and lock in that retinol or vitamin c serum you’re also using. Use them together. Daily.
  • Serums help with hydration; a key feature of ours is replenishing your NMF; but they’re not a replacement for your moisturizer.
  • Can you wear multiple serums at a time? Absolutely! See our note above.

62 reviews

100% of reviewers would recommend this product to a friend.






Smooth skin at last!

Have been using for just 2 weeks now, and it’s my favorite part of the morning! My skin has been so smooth and glowing - love this serum!!!

Fantastic product

I had patches of rosacea on my neck from using a retinol and this serum instantly soothed it. In combination with the moisturiser the skin feels so hydrated and protected.

Pleasantly pleased

I do feel it's making a difference to the quality of my skin and making it more firm. I'm going to keep using it for sure.


I'm not sold on eighteen b yet- i've been using the firming serum and tried both the protein and hydrogel moisturizers for a few weeks now- my skin doesn't look or feel any better to me, but also not any worse (surprisingly didn't break out from any of the products). I'm going to try for a few more weeks.

magic in a bottle

I work in the beauty industry and have tried lots of products and potions. I started using this a few weeks ago and I love it. I will let you know how my skin keeps improving. And it is now one product instead of 4 every night.

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