How Long Does a Keratin Treatment Last? (And How to Make It Last Longer)

Quick answer: A professional keratin treatment usually lasts 3–5 months. A full Brazilian (Tanino) keratin lasts longest — up to around five months — while express or lighter smoothing treatments last about 6–12 weeks. The single biggest factor in how long yours lasts is aftercare: sulphate-free products and washing less often can push results well past the three-month mark.

“How long will it actually last?” is one of the first things Perth clients ask before booking keratin — fair enough, given the time and cost involved. Here’s a straight answer, what makes it fade faster, and exactly how to stretch your results.

How long does a keratin treatment last on average?

Most treatments last 3–5 months. As a general guide: a full Brazilian/Tanino keratin holds for around 3–5 months; a keratin smoothing treatment sits at the shorter end; and an express keratin typically lasts 6–12 weeks. Results fade gradually rather than dropping off suddenly, so there’s no harsh regrowth line.

What makes a keratin treatment fade faster?

• Sulphate shampoos — the number-one culprit; sulphates strip the treatment quickly.

• Washing too often — every wash shortens the lifespan.

• Chlorine and salt water — pools and the ocean break results down.

• High heat with no protection — repeated hot tools without a heat protectant.

• Hair type — fine hair tends to release the treatment faster than coarse hair.

How to make your keratin treatment last longer

• Switch to a sulphate-free shampoo and conditioner — the single most important step.

• Wash less often (aim for 2–3 times a week) and use dry shampoo in between.

• Follow your stylist’s first-wash timing — often 48–72 hours after treatment.

• Always use a heat protectant before styling.

• Sleep on a silk or satin pillowcase to reduce friction and frizz.

• Protect your hair from chlorine and salt water — wet it with fresh water first, or wear a cap, and rinse straight after swimming.

For the full routine, read our complete keratin aftercare guide.

Does keratin last longer on some hair types?

Yes. Coarse, thick hair generally holds a treatment longer, while fine hair tends to shed it faster. Your natural oil levels, how often you wash, and your local water all play a part — which is why two people can get different lifespans from the same treatment.

When should you rebook?

Plan a full treatment every 3–5 months, or an express touch-up sooner if you want to top up frizz control between full appointments. Regular, well-timed refreshes keep results consistent without over-treating your hair.

How long does keratin last? — FAQ

Can a keratin treatment last 6 months?

With excellent aftercare — sulphate-free products and infrequent washing — some clients get close to six months from a full treatment, but 3–5 months is the realistic average.

Does keratin wash out completely?

It fades gradually as you wash, returning your hair to its natural texture over time. There’s no harsh line or sudden change.

How soon can I wash my hair after keratin?

Usually 48–72 hours, depending on the formula — follow your stylist’s advice. Some organic treatments allow same-day washing.

Will one keratin treatment straighten my hair permanently?

No — keratin is semi-permanent. It smooths and reduces frizz for a few months, then wears off. See our guide on whether a keratin treatment is worth it.

Book your keratin treatment in Leederville

We give every client a full aftercare plan so you get the longest possible results. Iza Clarke Hair & Beauty is a Leederville salon recognised by the 2026 Quality Business Awards as Best Hair Salon in the City of Vincent, using an organic, formaldehyde-free formula. Explore our Brazilian keratin treatment in Perth, see how much it costs, call 0450 475 614, or book online.

298 Vincent Street, Leederville, Perth WA 6007.

Written by the team at Iza Clarke Hair & Beauty, Leederville — award-winning Perth keratin specialists. This guide is general information, not medical advice; for health questions about any hair treatment, speak with your healthcare provider.