Keratin vs Extenso
Nicolas AblittSalon Director
Published
Hello from Nicolas Ablitt Hair Studio. As the salon director here in Corringham, Essex, I'm often asked about the difference between Keratin smoothing treatments and our signature [Extenso smoothing service]([LINK: Extenso service page]) (which is not L'Oréal X-Tenso). Both leave hair smoother and frizz-free, but they work in very different ways and suit different needs.
Here's what each treatment actually does, how long it lasts, and how to decide which one is right for you.
In short
Keratin coats the hair to reduce frizz and adds shine for 8 to 12 weeks. It keeps your natural waves and curls. Extenso gently relaxes the internal bonds for naturally straight hair that lasts until it grows out. Keratin keeps the movement, Extenso removes most of it.
What is a Keratin smoothing treatment?
Keratin smoothing (sometimes called a Brazilian blow-dry) is a semi-permanent deep-conditioning treatment. It coats each strand with keratin, smoothing rough cuticles and reducing frizz by up to 85% while adding shine.
The treatment does not change your hair's internal shape, so natural waves or curls stay in place, just frizz-free and easier to style. Most clients find their hair dries faster and looks smoother afterwards.
Because keratin is a natural protein, the treatment is gentle and nourishing, with no harsh chemical restructuring. Modern formulas are formaldehyde-free and work well on coloured or mildly damaged hair.
You'll see results for around 8 to 12 weeks, and the treatment fades gradually without harsh regrowth lines. To keep it going, we recommend follow-up treatments every few months, along with sulphate-free shampoo and avoiding harsh chemicals or saltwater in the first couple of weeks.
What is Extenso smoothing?
Extenso smoothing, our salon's speciality, is a long-lasting treatment designed to give you smooth, straighter hair with a natural finish. It works by gently relaxing the hair's internal bonds. There are no drastic chemicals, but the results are far more permanent than keratin.
Your hair will be very straight and sleek initially, then settle into a beautifully smooth, naturally straight look after a couple of washes. You'll keep about 20% of its natural movement and volume, so it doesn't fall flat or lifeless.
Extenso is a permanent change. Treated hair stays straight until it grows out, and most clients need a root refresh every 4 to 6 months. We always assess hair condition first to make sure it's strong enough, and we'll steer clear if it's heavily damaged.
The process includes a 3-day setting period at home, with no tying or wetting. Once that's done, your hair stays sleek and wash-resistant, with no special products needed, though we still recommend a gentle, hydrating shampoo to maintain shine. Heat tools are optional. Your hair will dry straight on its own, but curls won't last as long afterwards.
Keratin vs Extenso: side-by-side comparison
| Feature | Keratin Treatment | Extenso Smoothing |
|---|---|---|
| How it works | Coats the hair with keratin and seals it in with heat. | Gently softens the internal structure of the hair to reduce curl. |
| Frizz control | Excellent. Lasts 8 to 12 weeks. | Long-lasting. Eliminates frizz until hair grows out. |
| Look and feel | Smooth with natural movement. | Sleek, soft, and straighter with subtle movement. |
| Longevity | 8 to 12 weeks. | 4 to 6 months or longer (only the root regrowth needs touching up). |
| Hair health | Nourishing. Adds shine and protein. | Gentle and effective when professionally applied. |
| Best for | Softening frizz and waves. | Straightening thicker, wavy or frizzy hair with a natural look. |
| Styling time | Reduced, but you'll still want to style. | Very low. Wash, dry, and go. |
| Price | Call the salon to book a consultation. | Call the salon to book a consultation. |
[Book a consultation]([LINK: booking URL])
Which treatment suits you best?
Choose Keratin if you want smoother, shinier hair but still like natural waves or curls. It's flexible, quick, and gentle on coloured or slightly damaged hair.
Choose Extenso if you crave smooth, straight hair that lasts and frees up morning styling time. It's ideal for thicker, frizzier hair that needs serious taming.
Hair condition matters. If your hair is very fragile or heavily bleached, Keratin is often the better starting point. We'll advise on the right course during your [consultation]([LINK: contact / consultation page]).
Commitment and frequency. Keratin needs re-treating roughly 3 to 4 times a year. Extenso needs fewer visits, maybe once or twice a year, depending on regrowth.
We tailor our advice to your hair goals, lifestyle, and budget.
Local advice for Corringham clients
We get plenty of brides and mums of brides walking in from Corringham High Street in July humidity asking how to stop their hair frizzing for the photos. This is the conversation we have most often, and the answer usually depends on how much of the natural movement they want to keep.
Clients aged 40 to 60 often tell us their hair feels years younger post-treatment. Shiny, obedient, and easy to manage. Extenso is our go-to for those who want consistent, effortless style day after day. Keratin is still an excellent smoother, especially if you want to retain movement or have more delicate hair.
Frequently asked questions
How long does each treatment take in the salon?
Keratin treatments typically take 2 to 3 hours, depending on hair length and thickness. Extenso usually takes 3 to 4 hours. We'll give you an accurate time at your consultation.
Will my hair feel different to the touch?
Yes, in a good way. Both treatments leave hair noticeably softer and smoother. Keratin adds a slight protein-rich feel. Extenso leaves hair feeling sleek and weightless.
Can I have Extenso if my hair is coloured or highlighted?
In most cases, yes, but we'll always assess hair condition first. Heavily bleached or compromised hair may need to start with Keratin instead.
How soon can I wash my hair afterwards?
With Keratin, we recommend waiting 48 to 72 hours. With Extenso, there's a strict 3-day setting period where the hair can't be tied up or wet.
Is there any smell or downtime?
Modern Keratin formulas are formaldehyde-free, so there's no harsh smell and no downtime. Extenso has minimal odour and the only "downtime" is the 3-day setting period when the hair needs to be left loose and dry.
Ready for frizz-free, gorgeous hair?
If you're dreaming of hassle-free hair that looks and feels amazing, [book a one-on-one consultation]([LINK: booking URL]) at Nicolas Ablitt Hair Studio in Corringham, Essex. We'll assess your hair, talk through what matters most to you, and recommend the right path, whether that's Keratin, Extenso, or a tailored plan combining both.
Most clients tell us their mornings feel a lot easier afterwards, and the school run no longer needs the GHDs.