No. 9 Bond Protector Nourishing Hair Serum — Reddit Reviews
by Olaplex
Updated November 10, 2026
Lightweight serum tames humid frizz, flyaways, and curls; heat-styling favorite, limited moisture.
What the community says
A lightweight serum-style leave-in for damp hair, it adds slip, smooths frizz, and layers easily before blow-drying or air-drying. Fine-haired users often prefer its weightless styling feel, though dry lengths may need another moisturizer and sensitive scalps can react.
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Full ingredient list · 31
Olaplex No. 9 Bond Protector Nourishing Hair Serum ingredients
Water/Aqua/Eau, Propanediol, Betaine, Quaternium-22, Bis-Aminopropyl Diglycol Dimaleate, Sodium Hyaluronate, Cetrimonium Chloride, Panthenol, Hydroxyethylcellulose, PVP, Guar Hydroxypropyltrimonium Chloride, Furcellaria Lumbricalis Extract, Pelvetia Canaliculata Extract, Xylitylglucoside, Polyquaternium-44, Anhydroxylitol, Maltitol, Citric Acid, Trisodium Ethylenediamine Disuccinate, Xylitol, Ethylhexylglycerin, Sodium Hydroxide, Sorbic Acid, Phenoxyethanol, Sodium Benzoate, Fragrance (Parfum), Citral, Citronellol, Hexyl Cinnamal, Limonene, Linalool
Listed in label order, highest concentration first. Linked ingredients have their own page.
Real Reddit threads — 51 mentions across 19 threads
Olaplex No. 9 Bond Protector Nourishing Hair Serum on Reddit, in one place — 19 threads from r/Naturalhair, r/HaircareScience and 3 more, summarized.
“I blow dry with Olaplex #9 and a few drops of the Olaplex hair oil.”
Positive
“I use a cream based protectant (usually number 6 and 9 Olaplex) before blow drying”
Positive
“a tiny bit of olaplex 9 mixed in with morrocan oil volumizing mousse.”
Positive
“then after 4 minutes I use Olaplex No.9, style my hair and finish with No.7 oil.”
Positive
“I've found that No. 9 (the serum) helps keep moisture in as a leave-in”
Positive
“Yes it can help with that! No. 3 would definitely work for this purpose, and I've found that No. 9 (the serum) helps keep moisture in as a leave-in”
Positive
“Olaplex no9 is also amazing for smoothing away the flyaways, and is also a great heat protectant”
Positive
Dupes & Alternatives
Often paired with
Products Redditors use alongside this one
Olaplex
Mentioned together in 16 threads
“My favorites so far are Olaplex No. 9 and Sutra Beauty leave in. I also use the Olaplex hair oil, 3-4 drops for my entire head.”