
The Leave-In Hair Treatment
- Replenishes and smooths strands, boosts shine, tames frizz, and strengthens hair without weighing it down.
- Helps to support natural hair growth while preventing shedding and breakage.
- Helps to reverse brittle or weakened hair - renewing strands, improving hair thickness, and noticeably reducing the appearance of split ends.
- Ultra-nourishing and hydrating seals in nutrients and helps the hair retain moisture for silky locks with a healthy bounce.
- Softens and detangles hair for easier combing and reduced breakage.
- Combats damage caused by daily styling, color processing, chemical treatments, and environmental aggressors - for stronger, shinier, more resilient hair.
- Ingredients that support improved scalp health with soothing, fortifying, and anti-inflammatory properties.
- 100% agree hair looks and feels healthier after use
- 90% agree The Leave-In Hair Treatment helps repair hair from heat
- 97% agree hair feels easier to manage/style after use
- See clinical and user trials.
- Ultra-nourishing, and fast-absorbing. Residue-free and does not weigh down hair.
- Formulated without irritants, allergens, silicones, parabens, or sulfates. Fragrance-free.
- Suitable for all hair types. Vegan.
- See ingredients.
How To Apply
Apply a small amount to clean, dry or towel-dried hair. Using fingertips or The Neem Comb, work from the scalp or midlength to the end of hair, focusing on areas of need. Allow hair to dry naturally, or blow dry for an enhanced finish.
- Use 2 to 3 times per week as needed.
- For best results, use in conjunction with the Augustinus Bader haircare system: The Shampoo, The Conditioner, The Scalp Treatment, and The Hair Oil.
- Suitable for all hair types.
Clinically Proven Results





The Leave-In Hair Treatment
The Leave-In Hair Treatment increased hair shine by
330%
The Leave-In Hair Treatment increased hair strength by
182%
The Leave-In Hair Treatment increased hair count by
31%
Explore All Results
The Leave-In Hair Treatment increased hair hydration by 115%
The Leave-In Hair Treatment increased hair shine by 330%
The Leave-In Hair Treatment increased hair smoothness by 185%
The Leave-In Hair Treatment decreased hair follicle clog by 100%
The Leave-In Hair Treatment increased hair strength by 182%
The Leave-In Hair Treatment increased hair count by 31%
The Leave-In Hair Treatment reduced broken and damaged hair from brushing by 93%
The Leave-In Hair Treatment increased hair strand thickness by 138%
*In an 12-week Clinical Trial of 35 women and men with all hair types.
User Proven Results
100% agree hair looks healthier after use.
100% agree overall hair health and quality is improved.
99% agree hair feels nourished after use.
100% agree hair feels stronger after use.
97% agree The Leave-In Hair Treatment makes hair shinier.
97% agree their hair looks smoother.
96% agree The Leave-In Hair Treatment helps their hair color appear more vibrant.
95% agree The Leave-In Hair Treatment enhances their hair's natural texture.
99% agree that hair looks and feels renewed and restored after use.
92% agree The Leave-In Hair Treatment helps repair hair from color damage.
93% agree frizz is reduced/tamed.
94% agree hair breakage is decreased.
90% agree The Leave-In Hair Treatment helps repair hair from heat.
93% agree The leave-in Hair Treatment repair split ends.
97% agree hair feels easier to manage/style after use.
96% agree The Leave-In Hair Treatment does not leave residue on hair.
95% agree The Leave-In Hair Treatment helps reduce styling time.
95% agree The Leave-In Hair Treatment detangles hair.
94% agree The Leave-In Hair Treatment helps reduce drying time.
**In an 12-week Consumer Perception Study of 105 women and men with all hair types.
Key Ingredients
Augustinus Bader haircare is formulated with sustainably-sourced, high potency botanicals and bio-engineered clean actives where possible, to reduce environmental impact.
The Leave-In TreatmentPowered by our patented TFC8® technology and formulated with potent hair superfoods and anti-oxidants including Neem Extract, Shikakai Extract, and Rambutan Extract to fortify and thicken tresses while actively protecting strands against daily damage.
See all ingredients | Free From ListOur skincare is 100% free of parabens, fragrance, SLS, SLES, DEA, heavy metals, talc, and petrolatum/paraffin/mineral oil and formulated without unnecessary preservatives, solvents, or emulsifiers.
Aqua/Water/Eau, Glycerin, Cocos Nucifera (Coconut) Oil, Ricinus Communis (Castor) Seed Oil, Behenyl Alcohol, Sodium Acrylates Copolymer, Citric Acid, Maltodextrin, Xanthan Gum, Argania Spinosa Kernel Oil, Panthenol, Avena Sativa (Oat) Kernel Oil, Hydrolyzed Vegetable Protein, Potassium Sorbate, Saccharide Isomerate, Hydroxypropyl Guar Hydroxypropyltrimonium Chloride, Lecithin, Sodium Benzoate, Hydrolyzed Rice Protein, Sodium Phytate, Acacia Concinna Fruit Extract, Melia Azadirachta Leaf Extract, Tocopherol, Helianthus Annuus (Sunflower) Seed Oil, Sodium Hydroxide, Nephelium Lappaceum Seed Extract, Caesalpinia Spinosa Fruit Pod Extract, Biotin, Camellia Sinensis Leaf Extract, Hydrogenated Lecithin, Tocopheryl Acetate, Helianthus Annuus (Sunflower) Sprout Extract, Sodium Citrate, Alanyl Glutamine, Arginine, Oligopeptide-177, Sodium Chloride, Sorbic Acid, Phenylalanine, Sisymbrium Irio Seed Oil, Bambusa Arundinacea Stem Extract, Hippophae Rhamnoides Fruit Extract.

Just as our hero skin products provide cells with a repair toolbox, The Leave-In Hair Treatment is a complete array of highly effective ingredients that remind hair follicle cells of their innate ability to regrow and renew the hair. The presence of our proprietary technology, TFC8®, ensures that nutrients are delivered precisely where they are needed to awaken the youthful behavior of healthy, thriving hair.
Professor Augustinus Bader Read About Professor BaderThe lip balm is the creamiest, most nourishing I've tried!
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Frequently Asked Questions
"The Leave-in Hair Treatment is 100% vegan and free of gluten, GMOs, parabens, silicones, sulfates (SLS, SLES), DEA, fragrance, heavy metals, talc, and petrolatum/paraffin/mineral oil. "
Housed in a 100% recyclable tube made from sustainable sugar cane and 100% recyclable cap. Carton and leaflet are FSC-certified and recyclable.
Yes, it's a sulfate-free formula design to maintain your hair color. If you have any concerns, we recommend consulting your hairstylist before use.
Yes, The Leave-in Hair Treatment is safe to use in pregnancy and breastfeeding.
The Leave-in Hair Treatment is unscented, with no fragrance added.
The Leave-In Hair Treatment should last around 2-3 months.
The Leave-in Hair Treatment can be used 2-3 times per week as needed.
The Leave-in Hair Treatment boosts hair-healthy properties of The Conditioner, further enhancing hair's natural growth, strength, shine, and resilience. The Leave-in Treatment offers an instant refresh at any point throughout the day.
The Leave-in Hair Treatment boosts hair-healthy properties of The Conditioner, further enhancing hair's natural growth, strength, shine, and resilience. The Leave-in Treatment offers an instant refresh at any point throughout the day.
Yes, The Leave-in Hair Treatment can be used on both dry and damp hair.
The Leave-in Hair Treatment contains multiple powerhouse ingredients that protect against heat and combat damage caused by heat.
If you have any concerns, we recommend consulting your hairstylist before use.
The Leave-in Hair Treatment contains ingredients that offer natural protection against UV.
Pairs Well With
The Leave-In Hair Treatment pairs well with the following products for your haircare routine