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  • L'Oréal Professionnel Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* 200ml
Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing*
Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing*

L'Oréal Professionnel Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* 200ml

%0 4.6 | 48 reviews
+Offer
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£32.00 (£0.16 per ml)

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Earn 32 points with My Sephora

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L'Oréal ProfessionnelKeratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing*
£32.00
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L'Oréal Professionnel Keratin Alpha Sleek Smooth Transformer- 2 week Frizz Control & smoothing* Hair Treatment 200ml

Keratin Alpha Sleek Smooth Transformer is a Professional Smoothing Treatment formulated with Keratin-Alpha shapers and Amino.

Reprograms hair for up to 2 weeks of frizz control1
•\tUp to 5x smoother hair and 2x less frizz2
•\tControls unwanted volume for daily styling in half the time3
•\tAfter 4 uses, the Smooth Transformer resets hair discipline¹ at the Keratin Alpha level for a total fibre transformation⁴.
•\tProvides up to +77% instant shine⁵
•\t 73% of women saying they have never achieved this level of smoothness with their regular routine, and 82% saying their hair has never been so quick to style⁶.

Use treatment once a week after shampoo. Performance peaks after 4 weeks. Alternate with our hair mask on other wash days of the week. Shake well before use. Section hair into 2 and apply evenly from lengths to ends on each section. Use 30-50 grams per use depending on hair thickness and length. Leave on for 10-15 minutes- no longer & rinse. Complete the routine with Keratin Alpha Sleek Serum.

¹Instrumental test after 4 uses of Smooth Transformer. ²Instrumental tests with routine 4 times of Shampoo + Smooth Transformer + Leave-on. ³ Consumer test on 68 participants, 1 application/week for 4 weeks. Based on a 15-day break observation. ⁴Instrumental and consumer tests. ⁵Instrumental tests after one use of Smooth Transformer. ⁶Consumer tests. 67 participants. After 4 uses of Smooth Transformer.

Directions

Use once a week maximum. Section hair into 2 and apply evenly from lengths to ends on each section. Use 30-50 grams per use depending on hair thickness and length. Leave on for 10-15 minutes (IMPORTANT - NO LONGER), and rinse.

Ingredients

1258152 S3 - INGREDIENTS: AQUA / WATER / EAU • CETEARYL ALCOHOL • COCOS NUCIFERA OIL / COCONUT OIL • BEHENTRIMONIUM CHLORIDE • ISONONYL ISONONANOATE • CETYL ESTERS • PARFUM / FRAGRANCE • ETHANOLAMINE • ISOPROPYL ALCOHOL • CYSTEINE • DIMETHICONE • HYDROXYETHYLCELLULOSE • PHENOXYETHANOL • SODIUM METABISULFITE • AMODIMETHICONE • ASCORBIC ACID • TRIDECETH-10 • TRISODIUM ETHYLENEDIAMINE DISUCCINATE • PEG-100 STEARATE • ROSE KETONES • STEARETH-6 • TAURINE • TRIDECETH-3 • GLYCERIN • BUTYLENE GLYCOL • DISODIUM PHOSPHATE • ACETIC ACID • POLYSORBATE 60 • SODIUM PHOSPHATE • CARBOMER • SODIUM LACTATE • POLYSORBATE 20 • PALMITOYL TRIPEPTIDE-1 • PALMITOYL TETRAPEPTIDE-7 (F.I.L. N70068431/1).

This list of ingredients may be subject to change, please consult the packaging of the product purchased.

Bundle

25% SAVING. When you buy two qualifying L'Oréal Professionnel products.*

*Simply add two qualifying L'Oréal Professionnel products fulfilled by SEPHORA UK to your Shopping Bag and the discount will automatically apply at checkout. One offer bundle per order. Valid until the 13th July or whilst stock lasts. Cannot be used in conjunction with any other promotional discount. Offer is not applicable to pending purchases or previously made purchases.

Shop this offer

25% SAVING. When you buy two qualifying L'Oréal Professionnel products.*
Free Gift

FREE Absolut Repair Molecular Mini Rinse-off Serum 75ml when you spend £38 on L'oreal Professionel.*

*One free gift per order. Valid until the 13th of July or whilst stock lasts. Your free gift will automatically add to the shopping bag page. Total at order summary must be £38 or more worth of L'oreal Professionel products, after any Promotion Code, Brands You Love discount and before delivery charges are applied. Cannot be used in conjunction with any other Promotion and this offer is not applicable to previously made or pending purchases. 

Shop this offer

FREE Absolut Repair Molecular Mini Rinse-off Serum 75ml when you spend £38 on L'oreal Professionel.*
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Rated 3 out of 5 by from Stinky but good This works, it’s not very hydrating though and I find that my hair has no slip when using this which makes it difficult to actually apply it to every strand. It also smells bad, though not as potent as the serum. I’d repurchase the treatment over the serum purely over the smell. Though despite this it does leave my hair very smooth afterwards.
Date published: 2026-06-21
Rated 4 out of 5 by from Frizz control and sleek hair! [This review was collected as part of a promotion.] I used this product once a week for four weeks. My hair is regularly bleached and coloured in a salon. I found that this Keratin mask helped moisture my hair post chemical treatment. It kept on top of the frizz and prevented any further breakage. My hair felt visibly sleeker and healthier after using it. The smell was subtle and not overpowering. As I have chin length hair, I did not need a lot of the product so, a little went a very long way. I am very glad I was given the opportunity to test this product because it really benefited my hair.
Date published: 2026-03-26
Rated 4 out of 5 by from Luxurious [This review was collected as part of a promotion.] A really luxurious feeling hair treatment that doesn’t leave the hair feeling greasy or heavy. Sometimes I find that treatments are really hard to wash out and leave almost a filmy texture on my hair but I didn’t experience it with this. I’m looking forward to using it in the middle of summer when my hair is a frizzy mess !
Date published: 2026-03-19
Rated 5 out of 5 by from You have to try!!! [This review was collected as part of a promotion.] I've been using Loreal Keratin Alpha Sleek Smooth Transformer Treatment for almost 40 days now and I am really surprised by the results so far! It's totally amazing! Made my hair more sleek, soft and looks healthy! I also love the scent! Gonna absolutely keep using it.
Date published: 2026-03-19
Rated 5 out of 5 by from It’s helps for frizzy hair but not for long as I’m [This review was collected as part of a promotion.] The texture is lightweight very creamy . As soon as you cream your hair with it , hair feels very soft straight away. Needed to keep it for 15 minutes for best results. After straightener results feels more better looks sleek , shinny. Frizziness control is depends on how often you wash your hair. Overall I would recommend this product for people who have struggle with frizziness .
Date published: 2026-03-17
Rated 3 out of 5 by from Some improvement [This review was collected as part of a promotion.] This treatment is just part of a routine used to improve smoothness, ease of styling and cancel frizz, therefore i can’t comment on the full routine or other products. To begin, i would say the design of the product is modern and sleek, the purple colour is quite luxurious. The consistency of the cream itself is not what i would normally add to my hair. I left it for 12 minutes and rinsed. My hair didn’t feel very soft at this stage. Later, when drying it, it felt matted and dry in some parts. However once dry it did feel light and sleek. Overnight and through a gym session it continued to feel great. However, i had to deduct marks for the smell. This really, really does not smell good and this smell lingers for days, which is important to me and would put me off purchasing again.
Date published: 2026-03-10
Rated 5 out of 5 by from Doesn’t weigh down my hair! [This review was collected as part of a promotion.] Recently added this into my hair routine and I am enjoying it so far. My hair is quite thin, wavy and gets really frizzy so i am always trying new things to see if they help me manage my hair even a little bit. This one was quite nice to use my hair felt so smooth and shiny and less puffy/frizzy after drying. My waves were still there but they looked more defined. One thing i was worried about was it making my hair flat because my hair is really fine and sometimes smoothing products can do that but this one doesn’t. It doesn’t feel heavy or greasy. The frizz isn’t completely gone but its definitely more manageable. I have only been using it for a short while though so I’m still figuring out how much works best for my hair but so far it has been a nice addition in my routine.
Date published: 2026-03-05
Rated 5 out of 5 by from Fantastic product. Does exactly what it’s meant to [This review was collected as part of a promotion.] I love a good hair treatment and as I’m prone to naturally frizzy hair it’s hard to find a good product which can make my hair look sleek and healthy all around without the feeling of stickiness and residue on the hair. L’Oréal keratin alpha sleek does just the job. Left my hair feeling soft and polished with no fly-aways. I will definitely be using this for my long hair health journey.
Date published: 2026-03-04
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