Olaplex’s New Serum Is My Secret Weapon for the Softest Silk Press Ever

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Olaplex No. 9 Bond Protector Nourishing Hair Serum

Olaplex No. 9 Serum


What We Like
  • Lightweight finish

  • Subtle, citrusy scent

  • Affordable price point 

  • Inclusive to all hair types

What We Don't Like
  • Not Byrdie clean

Olaplex's No. 9 Bond Protector is an all-star heat protectant that trimmed down my blowdry time and left me with my smoothest silk press ever.


Olaplex No. 9 Bond Protector Nourishing Hair Serum

Olaplex No. 9 Serum


We put the Olaplex No. 9 Bond Protector Nourishing Hair Serum to the test after receiving a complimentary sample from the brand. Keep reading for our full product review.

Olaplex was always my haircare white whale. I’ve been privy to the mythology surrounding their bond-building system for years now but never got around to actually sampling the line. When it first came on my radar, I was told that the brand’s formulas are tailored to color-treated hair, which, at the time, didn’t apply to me. Then, as the bond-building buzz grew to more of a roar, I assumed that it was a product strictly for straighter textures. As a Black woman, that’s often the caveat that accompanies buzzy hair trends: It’s great, but it wouldn’t work on your hair. But that was soon dispelled, too, as more Black women with similar hair types to mine came out as Olaplex enthusiasts.

The ninth addition to their numbered lineup was a belated but fitting place for me to get my first Olaplex experience, and it was worth the wait. From the first time I incorporated their No. 9 Bond Protector Nourishing Hair Serum into my blowdry routine, I’ve been able to give myself salon-quality silk presses from home. Where other serums left my hair feeling weighed down and greasy, No. 9 gave me the easy, breezy bounce that I’ve been chasing since I started doing my own blowouts—plus, it’s shielding my hair from pollution. Keep reading to find out why it’s earned a spot on my haircare holy grail.

Olaplex No. 9 Bond Protector Nourishing Hair Serum

Best for: A variety of hair types, especially hair that has been damaged by heat tools.

Uses: A leave-in styling serum that protects hair from the effects pollution, shields it from breakage and acts as a heat protectant.

Potential allergens: Not likely

Active ingredients: Bis-aminopropyl diglycol dimaleate (Olaplex’s patented bond-building ingredient), red algae extract, sodium hyaluronate, panthenol

Clean?: No; contains quaternium-22

Price: $28

About the brand: Founded in 2014, Olaplex has made a name for itself in the haircare industry by creating a patented technology, bis-aminopropyl diglycol dimaleate, best known as the brand's “secret sauce” for repairing bond breakage in hair. Its products have transformed the outcome of hair coloring in salons as well as proven to reduce damage in hair overall.

About My Hair: Heat damage and tired curls

Years of heat styling have left my 3C/4A hair less than stellar. Last fall, I cut my hair into a chin-length bob to get rid of scraggly, overprocessed ends, and although that brought many of my curls back to life, it didn’t solve all of my problems. Since the hair that is typically my leave-out for a sew-in—the strands along my hairline and center part—comes into contact with hot tools more than the rest of my locs, that’s easily where I see the most damage. In fact, the curls nearest to my forehead have entirely lost their pattern and can’t hold a curl. Because of this, I’m very particular with leave-ins and heat protectants. Even if I risk giving my blowout a greasy finish, I’m prone to glob heat protectant on to save what’s left of my curls. 

When I am wearing my hair straight, I’m flat ironing it at least every few days (I’m bad, I know), but for the most part, I keep it tucked away in protective styles like box braids, cornrows, and sew-in weaves. And to get the most out of my protective styles, I typically only wash my hair once each week. Before blowdrying and flat ironing my hair, I always make sure to apply a mask in lieu of conditioner and leave it on for way longer than prescribed. 

Olaplex no 9 serum texture on hand


The Feel: Smooth, not slimy

The name isn’t arbitrary: Olaplex’s No. 9 Bond Protector Nourishing Hair Serum has the same consistency as the serums on my nightstand, and one pump leaves you with a handful of thick product that melts down with ease. This formula is the perfect prelude to heat styling because it’s ultra-hydrating but not watery—like a face serum. This skincare-inspired detail is likely thanks to the sodium hyaluronate and panthenol, two all-star hydrators typically only seen on formula lineups for face products. 

The Results: Bounce and body-ody

When I first worked No. 9 into my blowdry, I was shocked by how fast my hair blew out. A silky-smooth blowout required way less heat than I typically use. In fact, a single pump shaved off one-third of the time that it usually takes to bring my hair from curly to kinky-straight and the finish was way flatter than I’m accustomed to getting with my blowdryer (I say flat in a positive way since the desired outcome for this look is sleek and straight). 

Even before breaking out my flat iron, my hair felt lightweight and bouncy. Stiff where? With just one pass of the straightener, I had a silk press that dreams are made of: It had movement, shine, and a silky texture. Plus, thanks to the fragrance, my hair smelt citrusy, not smokey. As per usual with my silk presses, I wrapped my hair before bed and was able to keep my silk press intact for at least five days each time I used No. 9.

The Value: A little goes a long way

For $28, you’ll be getting 3 ounces of Olaplex’s No. 9 Bond Protector Nourishing Hair Serum. But if that doesn’t sound like a lot, rest assured that this isn’t the type of product you’ll breeze through. I’m three blowdries in and typically very heavy-handed since I have thick hair, but I haven’t made a dent in the 3.0 fl. oz. bottle. Thanks to the airless pump, you don’t have to worry about spills or waste, so you can be sure that you’re getting the most out of the entire bottle. 

The time that I’ve saved on blowdries ups its value for me, too. Plus, the emphasis on hair health with pollution-protecting ingredients means that this is a product that will keep you from buying other products. 

Similar Products: You've got options

Oribe Power Drops Hydration & Anti-Pollution Booster, $58: If you’re all in on Olaplex but want a product with a more botanical ingredient list, Oribe’s Power Drops might scratch that itch. Moringa seed extract, watermelon, lychee, and edelweiss work alongside hyaluronic acid to protect hair from pollution and provide a hydration boost. However, this is significantly pricier than Olaplex No. 9.

R+Co On A Cloud Baobab Oil Repair Splash-On Styler $32: Though it doesn’t have Olaplex’s signature bond builder on the ingredient list, this R+Co leave-in uses baobab oil to repair hair bands and leave a similarly silky finish, with the added plus of pollution protection.

Olaplex no. 9 before and after

Sumiko Wilson

Our Verdict

After my first few pumps of Olaplex’s No. 9 Bond Protector Nourishing Hair Serum, I couldn't imagine life without it. The formula seals in moisture and keeps pollution at bay to give styles a smoother feel, a sleeker finish and boost overall hair health. I’m sure that I'd see optimal effects when used alongside the entire Olaplex system, but even on its own, it’s a standout, thanks to the speedier dries and bouncier blowouts. I’m breaking up with oily heat protectants for good. 


  • Product Name No. 9 Bond Protector Nourishing Hair Serum
  • Product Brand Olaplex
  • Price $28.00

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