Your hair is smooth, soft and frizz-free, and then the question comes up: how long will it stay like this? With a keratin treatment, the answer depends on the version you chose, on your hair type and above all on what you do at home. Below you will find how long keratin usually lasts, what shortens or extends it, and the aftercare that keeps the result looking good for months.
How long does keratin last?
There are two versions, and they differ quite a bit:
- Classic keratin treatment: 3 to 5 months. The treatment itself takes 2.5 to 4 hours and gives the longest-lasting result.
- Brazilian Blowout: 6 to 12 weeks. A lighter, quicker treatment of 1.5 to 2 hours. You can wash your hair the same day.
Worth knowing: keratin does not grow out in a hard line the way colour does. It rinses out gradually, so your hair slowly returns to its natural volume and frizz. Most people notice it first on humid days or around the hairline.
What decides how long the result lasts?
Two people who had the same treatment can look very different after three months. That comes down to:
- Your hair structure. Thick, porous or tightly curly hair takes keratin in well, but also releases it faster than fine, straight hair.
- How often you wash. Every wash takes a little of the treatment with it. Washing daily means the result fades sooner.
- Your shampoo. Sulphates and salt rinse the active ingredients out faster. This is the most common mistake after a keratin treatment.
- Chlorine and sea water. A week of swimming on holiday can cost you several weeks of wear.
- Heat without protection. Straighteners and curling tongs on a high setting dry the hair out.
- Colouring and bleaching. Another chemical process on top needs the right timing and spacing.
The first 72 hours matter most
After a classic keratin treatment, the keratin needs time to set inside the hair fibre. So leave your hair alone for 72 hours:
- do not wash it and keep it dry, including rain, sweat and saunas;
- do not tie it up: no bun, no clips, no hair ties;
- no cap or headband that creases the hair;
- do not tuck your hair behind your ears, as that leaves a kink too;
- do not start new products, only what we recommend.
With the Brazilian Blowout there is no waiting time: you can wash your hair the same day. That makes it practical if you are short on time or want to see how smooth hair feels before committing to the longer version.
Your routine at home after the first week
From then on, your routine decides how long you enjoy the result. What makes the difference:
- Wash with a sulphate-free shampoo and always follow with a conditioner or mask.
- Do not wash daily. Two or three times a week is enough for most hair types.
- Use lukewarm water rather than hot, and rinse thoroughly.
- Blot your hair dry with a microfibre towel or a cotton T-shirt instead of rubbing it.
- Always use a heat protectant before blow-drying or styling.
- Protect your hair from chlorine and salt water: wet it with tap water and apply a leave-in before you go in.
- Use a nourishing mask once a week and give it a few minutes to work.
Extending the result between treatments
You do not have to wait until the keratin has rinsed out completely. A Brazilian hair ritual is an intensive conditioning treatment of 45 to 75 minutes that you can repeat in between. With heat and nourishing masks, your hair gets moisture, nutrition or repair, depending on what it needs at that moment.
The idea comes from the Brazilian cronograma capilar, a schedule that alternates hydration, nutrition and repair. Well-nourished hair holds a keratin treatment noticeably longer. For curly hair that dries out quickly between treatments, this ritual is usually the easiest win.
When is it time for a new treatment?
Watch for these signs:
- frizz returns on rainy or humid days;
- blow-drying takes noticeably longer than it did a month ago;
- the ends feel dry and look dull;
- your natural wave or curl comes back unevenly.
How soon you can repeat it depends on the condition of your hair. Every new appointment starts with a hair analysis: we look at structure, thickness and condition, and then choose the version that fits.
Frequently asked questions
Can I colour my hair after a keratin treatment?
You can, but the order and the timing matter. Colour usually works best before the keratin treatment or a few weeks afterwards. Let us know in advance so we can plan it in the right order.
How often can I repeat keratin?
As soon as the result starts to fade, the treatment can be repeated. In practice that means two or three times a year for the classic version and a little more often for the Brazilian Blowout. We always check first whether your hair is ready for it.
Which shampoo should I use?
A mild, sulphate-free shampoo without salt. That is the single most important step to keep the treatment from rinsing out early. During your appointment you get advice that suits your hair.
How much does a keratin treatment cost?
That depends on the length and thickness of your hair and on the version. Send us a photo of your hair on WhatsApp and you will get a personal price indication.
Want to know more?
Read more about the keratin treatment and Brazilian Blowout in Amsterdam or about the Brazilian hair ritual. Not sure which treatment suits you? Our article on keratin versus hair botox will help. Maria Bonita Hair works with clients in Amsterdam and Noord-Holland, Monday to Saturday from 10:00 to 19:00, by appointment only.
