Zoltan Hair · Mayfair · A Down treatment · permanent
Straightment Permanent
Straight, and it stays straight. No straighteners, no blow-dry, no bad-weather days — wash it and leave it. The hair I treat today stays straight for the rest of its life; only new growth comes in curly.
See prices & bookAll Down treatmentsby length and density
permanently
roots at 3–18 months
Before anything else
Everything you do to your hair costs it something. Including nothing.
This is the part most salons leave out, so I would rather you had it first.
Think about a bag you actually like
Not the one in the box — the one you have carried every day for three years. Rained on. Put down on the floor of the tube. Stuffed too full. Keys rattling around in it. It does not look like it did in the shop and it never will again. That is not neglect. That is what carrying it every day does.
Your hair has been with you far longer
The lengths on hair past your shoulders are often four, five, six years old — grown, then worn, every single day since. Rain. Sun. Hard London water. A hairband. A brush pulled through it when you are late. A towel. A pillow. A blow-dry. An iron at 200 degrees because it would not sit down otherwise. None of it dramatic, all of it adding up — and unlike skin, hair does not repair itself. What happens to it stays happened.
And you never notice you are doing it
Nobody stands at the mirror thinking that is damage. You put it up because it is windy. You go over it again because one bit will not sit down. You rub it dry because you are late. It is automatic, it is every day, and it is a couple of thousand small decisions a year that nobody counts. A treatment is the one thing on that list you actually decide to do — which is why it feels like the risky one, and why it gets all the blame.
So the honest question is not “will this damage my hair?”
Everything does. The question is what you spend, and what you get back for it.
Yes, it has a cost — and this one is a real one
This treatment breaks bonds and reforms them. That is not a coating and it is not reversible. It is the whole reason the result is permanent, and it is the reason this is the treatment I turn down most often.
What you get back
Hair that looks better, feels smoother and above all behaves — every day, without being fought. The shine is real and so is the manageability. What I will not claim is that it leaves your hair healthier than it found it. This one genuinely spends.
And the daily spend drops
Hair that lies down does not get gone over five times with an iron. Hair that is not fighting you does not get brushed hard when you are rushing. For a lot of people the damage they stop doing is larger than the damage I do — but on this treatment that is a calculation, not a slogan.
Which is why it needs hair that has it to spend
Some hair has already spent more than it had, and for that hair the answer is no, or not yet. Bleach history first, before anything else. You will get told honestly which one you are — and being told no here is me doing my job, not losing your business.
What I promise
The three numbers, honestly
This is the only treatment I offer that cannot be undone. So the promise is stated plainly, including the part people are not told.
Salon time
3 – 6 hours
Three hours on short hair, up to six on thick, curly, extra-long hair. It cannot be rushed — the whole result depends on section size and control, and hurrying is exactly how this goes wrong.
How much it takes out
80–100% of the curl
Genuinely straight. This is the one treatment where “straight” means straight, and it is permanent on every hair I touch today.
How long it lasts
Permanent — with a regrowth line
The part nobody mentions: the treated hair stays straight forever, but your roots grow in with their natural curl. Somewhere between three and eighteen months — depending on your growth and your pattern — there is a visible line where the two meet, and it needs redoing at the root. That is not a flaw, it is the nature of a permanent treatment — but you should know it before you book, not after.
What it actually does
This one does restructure the hair. There is no honest way to describe it otherwise.
It breaks the bonds and rebuilds them
A reducing agent breaks the disulfide bonds — the strong sulphur-to-sulphur links that hold your hair’s shape. The hair is ironed straight while those bonds are open, and a neutraliser then reforms them in the new position, locking it in. This is genuine chemical restructuring, not a coating.
Which is why the hair has to be able to take it
You are spending the hair’s structural reserve. Hair with healthy bonds has that to spend; bleached or over-processed hair does not. This is the treatment where I say no most often, and I would rather say it than take the booking.
And why it cannot be reversed
Once those bonds are reformed straight, they are straight. There is no undoing it and no growing it out of the treated length — you grow it out by cutting it off. Be certain before you sit down.
Why a treatment, rather than just looking after it better?
A fair question, and the honest answer is not the one that flatters me.
In an ideal world you would not need me
You would come in every few weeks for a conditioning treatment, and in between you would tie it up, air-dry it and leave it alone. That works. It genuinely does.
But almost nobody in London lives that way
Most of the people who sit in my chair are one of two. Either they can afford the upkeep and have not got the two hours a month — the standing appointment is the first thing cancelled, every time, because something at work moved. Or the time is not the problem and the money is, and a couple of hundred pounds a month on something that lasts three weeks is simply not a sensible way to spend it.
Either way you end up in the same place
Hair that never gets properly looked after, and gets fought with instead. Rushed. Ironed. Pulled up. Every day.
That is the actual case for this
One appointment, and the hair looks after itself for months. Not because it is magic and not because it is free — it costs your hair something and I have been straight with you about that. But it turns the upkeep from something you have to keep finding time and money for into something you did once. For most people that is the only version that survives contact with a real life.
And if you are someone who can do the standing appointment and the careful routine — tell me. That is a legitimate answer and I will say so.
In the chair
What actually happens on the day
Three to six hours, and every step matters.
1 · Read, clarify, and decide
The most important step on this page. I read pattern, frizz and damage, take the full colour and chemistry history, and decide whether this happens at all. If there is any doubt I test before anything else.
2 · Reduction
The reducing agent is applied and the disulfide bonds begin to open. Timed to the hair — over-processing here is irreversible, so it is checked repeatedly rather than left.
3 · Rinse
Rinsed thoroughly at the basin before anything else happens. Unlike the lighter treatments, this one is rinsed — leaving reducing agent in the hair while ironing would destroy it.
4 · The iron
Thin sections, controlled heat, the hair pressed straight while the bonds are open. This is where the shape is physically set, and where skill shows: section too thick and it will not take; too much heat on open bonds and the hair is gone.
5 · Neutralise
This treatment does need neutralising, and it is the step most often hurried. An oxidiser reforms the bonds in their new straight position and locks the result. Rushed or incomplete neutralisation is why some people’s permanent straightening drops or damages — it is not the reduction that fails, it is this.
6 · Finish
Rinsed, conditioned at a low pH and finished. You will leave with the final result — unlike the lighter treatments, there is no waiting to see how it settles.
What you actually get
Genuinely straight
Not smoothed, not softened. Straight, in rain, in humidity, at the gym, permanently, on every hair treated.
0 minWash and leave
The only treatment here where the honest answer is no styling at all. No straighteners, no round brush, no technique.
No more daily heat
You stop putting an iron through it every morning, which over a year is hundreds of passes the hair never takes.
A root appointment
The trade-off, stated plainly: somewhere between three and eighteen months the new growth needs doing, at roots-and-refresh pricing rather than full price.
Who it suits — and who it does not
This is the treatment where the answer is most often no. I would rather you heard that here than after paying for it.
Ideal
C4 – Z2 · damage at N
Tight curl through to coil, strong healthy hair with natural roots and ends, where you genuinely want straight and are done experimenting. Coarse resistant hair that nothing gentler holds.
Possible, with care
C5 – C6 · light colour, damage at ND
Looser patterns and lightly coloured hair can take this, but the strength and timing have to be exact, and I will often treat roots at full strength and the lengths far more lightly.
Usually no
Bleached, highlighted over 30%, or previously relaxed
Where the cystine has been oxidised to cysteic acid the damage is irreversible, and strong chemistry plus heavy tension on weak hair means breakage — sometimes catastrophic. Previous sodium hydroxide relaxer plus this chemistry is a genuine risk. Do not write it off or talk yourself into it from a web page. This is exactly what a consultation is for.
Book a mini consultation →No surprises
Things I would rather you heard from me than found out in the chair
None of this is in anybody else's brochure. It is all true, and knowing it in advance is the difference between a surprise and a plan.
It will smell
Anything heated to 200 degrees smells — think of food. Your own mousse or styling product on there smells too. Some treatments frankly smell like wet dog for a day. I work next to an open window and it clears, but I am not going to pretend it does not happen.
Some treatments shift your colour
Not all, but some will lift or warm what is already on your hair. If that applies to yours I will tell you before we start and we plan around it. I spent years as a colourist, so this is a conversation rather than a surprise at the mirror.
It can go flat
Certain hair looks bouncy for a fortnight and then sits down. I can usually work around it — leaving the roots alone, choosing a lighter strength, changing where I place the tension. But only if I know beforehand that volume matters to you. Say it at the consultation, not afterwards.
Damage is the thing we are trying not to do
These are chemical services and they are not free. Done properly on suitable hair the trade is small and worth it. Done wrong, or on hair that has already been through too much, it is breakage — which is exactly why sometimes the answer is no.
The first two visits, we are getting to know each other
This is the most useful thing on the page, and the thing almost nobody says out loud.
The first appointment is a learning appointment
I do not know your hair yet — and I do not know you. I know the chemistry; I do not yet know how yours takes it, what the last person left in it, or the life it has to survive. So I work carefully, and careful means slightly under rather than slightly over. On a permanent treatment that matters double: a section that held less than it should can be treated again; over-processed hair cannot be brought back.
Which is why the early check matters here
With a permanent result you see the truth in the first few washes. If a section has taken unevenly, tell me then — that is a conversation, not a complaint, and it is far better had in week two than month six. The root appointments afterwards are where the reading gets more precise each time.
My “perfect” and your “perfect” may not be the same thing
I might look at your hair and see a result I am pleased with — even, healthy, doing exactly what the chemistry should do. You might look in the mirror and want it flatter, or with more root movement left in. Neither of us is wrong. We are looking at different things — which on an irreversible treatment is exactly why the consultation takes as long as it takes.
So tell me, in your own words
Tell me what you want it to look like before we start — and on this treatment, tell me everything about the history first. What cannot be adjusted afterwards has to be right before. That is not pressure; it is the deal we both sign up to.
And the honest end of it: maybe I am not the right stylist for you. I am not saying I am — I am trying, and this is the one treatment where we find that out before anything irreversible happens, not after.
Whatever it is called elsewhere, this is the category.
Japanese straightening · Rebonding · Thermal reconditioning · Magic straight perm · Relaxer · Shukumo kyosei · Yuko
All permanent structural straightening, sold under different national and brand names. In Mayfair the branded versions run from £650 to £950, quoted as a range rather than a price.
Straightment Permanent is my own system, and every figure on this site is published. The chemistry and strength are chosen against your reading on the day. Read the rebonding family and Japanese systems guides for the full comparison — both free.
Colour
When to do your colour
With a permanent treatment this matters more than anywhere else, because you cannot undo either one.
Colour after, not before
Leave at least two weeks
The straightening comes first and the colour follows once it has settled. Colouring immediately beforehand adds processing to hair that is about to be structurally rebuilt.
Bleach is usually the end of the conversation
Not a scheduling question
Bleached or heavily highlighted hair generally cannot have this treatment at all — not a matter of order. If you want both, one of them has to give, and I will tell you which.
Tell me everything
Including years ago
Old relaxer, henna, metallic salts and box colour all change what is safe here, and some react badly with this chemistry. Anything you have forgotten is still in the hair.
Skin test
I do not routinely do one for straightening or perming, and there is no blanket UK requirement for these services — it is the product manufacturer and the insurer that drive it, not the law. Where a specific product calls for one, I will tell you and we will do it. Hair colour is a different matter: there it is effectively mandatory.
Strand and elasticity testing
Also not routine. I read the hair at the consultation and again on the day. Where I judge it necessary, I will say so before we start — and we test before anything else happens, rather than finding out halfway through.
What actually protects the hair
Knowing what has already been done to it. Colour history, previous chemistry and how it was cared for tell me more than any test — which is why I ask for the history before I ask what you want.
Making it last
The first 48 hours
Stricter than the lighter treatments, because the bonds are freshly reformed. Keep it loose and straight — no tight ties, no clips, no tucking behind the ears, nothing that puts a bend in it. A bend set now can stay.
What you wash it with
You do not have to give up lather. A gentle sulphate cleanser is fine; heavy strippers and salt-loaded formulas are what shorten a result. Two or three mild washes a week.
Not sure about yours? Send me a photo of the ingredient list and I will tell you whether to keep it.
The root appointment
Anywhere from three months to eighteen — a genuinely wide range, and it depends on how fast your hair grows, how tight your natural pattern is and how much the line bothers you. Tight curl at the root shows sooner; a looser pattern can go a year or more. Roots and refresh, not the full price — and the ends are not re-straightened, because they are already straight and re-processing them is how people damage their hair.
The terms, plainly
The same glossary appears on every treatment page here, so the language means the same thing wherever you read it — with what each term means for this particular treatment underneath.
pH
The acid-to-alkaline scale. Hair sits at about 4.5–5.5, slightly acidic. Alkaline products swell and open the cuticle so chemistry can get in — more change, more cost to the hair. Acid products close and smooth it — gentler, shinier, less penetration.
On Straightment Permanent: alkaline, roughly 8.5 to 9.5. The cuticle is swollen fully open so the chemistry reaches the cortex. Maximum change and maximum cost to the hair — which is why the hair has to be strong enough to start with.
Disulfide bonds
The strong, permanent sulphur-to-sulphur links. They give hair both its strength and its bounce. Hydrogen bonds, by contrast, are weak and temporary — broken by water and heat, which is why a blow-dry drops in the rain.
On Straightment Permanent: broken outright, 80 to 100% of them, and reformed straight. This is genuine restructuring, and it is the only treatment here that cannot be undone.
Porosity
How easily hair absorbs and holds water and chemicals. High porosity means a raised, damaged cuticle: it soaks product up fast and processes quickly and unevenly. Low porosity is resistant and needs more time.
On Straightment Permanent: the deciding factor. High porosity means it processes fast and unevenly — and on this treatment that is how hair is destroyed rather than merely disappointed.
Bounce (elasticity)
The ability to stretch and spring back, governed almost entirely by disulfide bond health. You can impose a shape on almost any hair. You cannot impose bounce — it has to be earned from healthy bonds.
On Straightment Permanent: removed by design. You are trading spring for straight, permanently, on every hair treated.
Reduction and neutralisation
The two-step chemistry of any perm or relaxer. Reduction breaks the bonds so the hair can be reshaped; neutralisation reforms them in the new shape and locks it in.
On Straightment Permanent: both, in full. Reduction opens the bonds, the iron sets the shape, neutralisation locks it. This is the step most often hurried elsewhere and the reason permanent straightening has the reputation it does.
Processing time
Timed to the hair, not to a clock on the wall. Porosity, texture and history all change how fast a treatment develops.
On Straightment Permanent: three hours on short hair, up to six on thick extra-long. It cannot be rushed.
Read further
Where this sits in the wider family
The free guides covering each tradition — what is in them, where they came from and who they suit.
Keratin & protein family
Every semi and demi-permanent smoothing treatment that coats and fills the hair rather than permanently restructuring it.
Open the guide →Brazilian & plastia
Nanoplastia, taninoplastia and their siblings — built on organic acids rather than aldehydes.
Open the guide →Japanese & Chinese systems
Shukumo kyosei, permanent thermal reconditioning, and the acid-heat systems built for damaged hair.
Open the guide →Rebonding family
Asia's structural straightening tiers, up to permanent pin-straight.
Open the guide →Korean systems
Magic straight, down perm, and the approach that straightens while keeping root lift.
Open the guide →The complete guide
Every smoothing and straightening treatment sold anywhere in the world, in one place.
Start here →Questions people actually ask
Is it really permanent?
On the hair I treat, yes — completely. What is not permanent is your head, because it keeps growing. New growth arrives with your natural curl, and somewhere between three and eighteen months the roots need doing — the range is that wide because growth rate and curl pattern differ enormously.
Will there be a line where it grows out?
Yes. This is the honest difference between this and Straightment Demi, which fades softly with no line at all. If a visible demarcation would bother you, Demi is the better treatment and I will say so.
Can I go back to curly afterwards?
Not on the treated hair. You grow it out by cutting it off. If you change your mind often between straight and curly, this is the wrong treatment for you — genuinely.
Does it damage my hair?
It restructures it, which costs the hair something — anyone who tells you otherwise is selling. Done on strong hair at the right strength, the result is straight, shiny and healthy for years. Done on hair that cannot take it, it is the most damaging thing in this trade. That judgement is what you are paying me for.
Why is it so much more expensive?
Three to six hours of one person’s undivided attention, and a process with no margin for error. It is also the only one you will not be repeating in full — after the first time you are paying roots-and-refresh prices.
Can I have it if I have had a relaxer before?
Tell me first, always. Hydroxide relaxer followed by this chemistry can dissolve hair. It is not automatically a no, but it is automatically a conversation.
Is it safe if I am pregnant or breastfeeding?
That is not my decision to make for you. I will give you the full ingredient list for the exact product I would use, so you can put it in front of your midwife, GP or pharmacist and decide with someone qualified.
How do I know I actually want this?
Start lighter. A good number of people who ask for permanent straightening are happier with Demi once they have lived with it — it gives them the manageability they were actually after, without the commitment or the line.
Real prices, published.
Four questions about your hair and the calculator gives you the exact price for your length and texture, and the appointment to book. No “from” prices that grow once you are in the chair.
See prices & bookAll Down treatmentsNot sure this is the right one? A mini consultation online is £9.95 — it is not a deposit and it does not come off the treatment, and every treatment includes a full consultation on the day at no charge.
Zoltan Hair · Mayfair · A Down treatment · permanent
Straightment Permanent
Straight, and it stays straight. No straighteners, no blow-dry, no bad-weather days — wash it and leave it. The hair I treat today stays straight for the rest of its life; only new growth comes in curly.
See prices & bookAll Down treatmentsby length and density
permanently
roots at 3–18 months
What I promise
The three numbers, honestly
This is the only treatment I offer that cannot be undone. So the promise is stated plainly, including the part people are not told.
Salon time
3 – 6 hours
Three hours on short hair, up to six on thick, curly, extra-long hair. It cannot be rushed — the whole result depends on section size and control, and hurrying is exactly how this goes wrong.
How much it takes out
80–100% of the curl
Genuinely straight. This is the one treatment where “straight” means straight, and it is permanent on every hair I touch today.
How long it lasts
Permanent — with a regrowth line
The part nobody mentions: the treated hair stays straight forever, but your roots grow in with their natural curl. Somewhere between three and eighteen months — depending on your growth and your pattern — there is a visible line where the two meet, and it needs redoing at the root. That is not a flaw, it is the nature of a permanent treatment — but you should know it before you book, not after.
What it actually does
This one does restructure the hair. There is no honest way to describe it otherwise.
It breaks the bonds and rebuilds them
A reducing agent breaks the disulfide bonds — the strong sulphur-to-sulphur links that hold your hair’s shape. The hair is ironed straight while those bonds are open, and a neutraliser then reforms them in the new position, locking it in. This is genuine chemical restructuring, not a coating.
Which is why the hair has to be able to take it
You are spending the hair’s structural reserve. Hair with healthy bonds has that to spend; bleached or over-processed hair does not. This is the treatment where I say no most often, and I would rather say it than take the booking.
And why it cannot be reversed
Once those bonds are reformed straight, they are straight. There is no undoing it and no growing it out of the treated length — you grow it out by cutting it off. Be certain before you sit down.
In the chair
What actually happens on the day
Three to six hours, and every step matters.
1 · Read, clarify, and decide
The most important step on this page. I read pattern, frizz and damage, take the full colour and chemistry history, and decide whether this happens at all. If there is any doubt I test before anything else.
2 · Reduction
The reducing agent is applied and the disulfide bonds begin to open. Timed to the hair — over-processing here is irreversible, so it is checked repeatedly rather than left.
3 · Rinse
Rinsed thoroughly at the basin before anything else happens. Unlike the lighter treatments, this one is rinsed — leaving reducing agent in the hair while ironing would destroy it.
4 · The iron
Thin sections, controlled heat, the hair pressed straight while the bonds are open. This is where the shape is physically set, and where skill shows: section too thick and it will not take; too much heat on open bonds and the hair is gone.
5 · Neutralise
This treatment does need neutralising, and it is the step most often hurried. An oxidiser reforms the bonds in their new straight position and locks the result. Rushed or incomplete neutralisation is why some people’s permanent straightening drops or damages — it is not the reduction that fails, it is this.
6 · Finish
Rinsed, conditioned at a low pH and finished. You will leave with the final result — unlike the lighter treatments, there is no waiting to see how it settles.
What you actually get
Genuinely straight
Not smoothed, not softened. Straight, in rain, in humidity, at the gym, permanently, on every hair treated.
0 minWash and leave
The only treatment here where the honest answer is no styling at all. No straighteners, no round brush, no technique.
No more daily heat
You stop putting an iron through it every morning, which over a year is hundreds of passes the hair never takes.
A root appointment
The trade-off, stated plainly: somewhere between three and eighteen months the new growth needs doing, at roots-and-refresh pricing rather than full price.
Who it suits — and who it does not
This is the treatment where the answer is most often no. I would rather you heard that here than after paying for it.
Ideal
C4 – Z2 · damage at N
Tight curl through to coil, strong healthy hair with natural roots and ends, where you genuinely want straight and are done experimenting. Coarse resistant hair that nothing gentler holds.
Possible, with care
C5 – C6 · light colour, damage at ND
Looser patterns and lightly coloured hair can take this, but the strength and timing have to be exact, and I will often treat roots at full strength and the lengths far more lightly.
Usually no
Bleached, highlighted over 30%, or previously relaxed
Where the cystine has been oxidised to cysteic acid the damage is irreversible, and strong chemistry plus heavy tension on weak hair means breakage — sometimes catastrophic. Previous sodium hydroxide relaxer plus this chemistry is a genuine risk. Do not write it off or talk yourself into it from a web page. This is exactly what a consultation is for.
Book a mini consultation →Whatever it is called elsewhere, this is the category.
Japanese straightening · Rebonding · Thermal reconditioning · Magic straight perm · Relaxer · Shukumo kyosei · Yuko
All permanent structural straightening, sold under different national and brand names. In Mayfair the branded versions run from £650 to £950, quoted as a range rather than a price.
Straightment Permanent is my own system, and every figure on this site is published. The chemistry and strength are chosen against your reading on the day. Read the rebonding family and Japanese systems guides for the full comparison — both free.
Colour
When to do your colour
With a permanent treatment this matters more than anywhere else, because you cannot undo either one.
Colour after, not before
Leave at least two weeks
The straightening comes first and the colour follows once it has settled. Colouring immediately beforehand adds processing to hair that is about to be structurally rebuilt.
Bleach is usually the end of the conversation
Not a scheduling question
Bleached or heavily highlighted hair generally cannot have this treatment at all — not a matter of order. If you want both, one of them has to give, and I will tell you which.
Tell me everything
Including years ago
Old relaxer, henna, metallic salts and box colour all change what is safe here, and some react badly with this chemistry. Anything you have forgotten is still in the hair.
Skin test
I do not routinely do one for straightening or perming, and there is no blanket UK requirement for these services — it is the product manufacturer and the insurer that drive it, not the law. Where a specific product calls for one, I will tell you and we will do it. Hair colour is a different matter: there it is effectively mandatory.
Strand and elasticity testing
Also not routine. I read the hair at the consultation and again on the day. Where I judge it necessary, I will say so before we start — and we test before anything else happens, rather than finding out halfway through.
What actually protects the hair
Knowing what has already been done to it. Colour history, previous chemistry and how it was cared for tell me more than any test — which is why I ask for the history before I ask what you want.
Making it last
The first 48 hours
Stricter than the lighter treatments, because the bonds are freshly reformed. Keep it loose and straight — no tight ties, no clips, no tucking behind the ears, nothing that puts a bend in it. A bend set now can stay.
What you wash it with
You do not have to give up lather. A gentle sulphate cleanser is fine; heavy strippers and salt-loaded formulas are what shorten a result. Two or three mild washes a week.
Not sure about yours? Send me a photo of the ingredient list and I will tell you whether to keep it.
The root appointment
Anywhere from three months to eighteen — a genuinely wide range, and it depends on how fast your hair grows, how tight your natural pattern is and how much the line bothers you. Tight curl at the root shows sooner; a looser pattern can go a year or more. Roots and refresh, not the full price — and the ends are not re-straightened, because they are already straight and re-processing them is how people damage their hair.
The terms, plainly
The same glossary appears on every treatment page here, so the language means the same thing wherever you read it — with what each term means for this particular treatment underneath.
pH
The acid-to-alkaline scale. Hair sits at about 4.5–5.5, slightly acidic. Alkaline products swell and open the cuticle so chemistry can get in — more change, more cost to the hair. Acid products close and smooth it — gentler, shinier, less penetration.
On Straightment Permanent: alkaline, roughly 8.5 to 9.5. The cuticle is swollen fully open so the chemistry reaches the cortex. Maximum change and maximum cost to the hair — which is why the hair has to be strong enough to start with.
Disulfide bonds
The strong, permanent sulphur-to-sulphur links. They give hair both its strength and its bounce. Hydrogen bonds, by contrast, are weak and temporary — broken by water and heat, which is why a blow-dry drops in the rain.
On Straightment Permanent: broken outright, 80 to 100% of them, and reformed straight. This is genuine restructuring, and it is the only treatment here that cannot be undone.
Porosity
How easily hair absorbs and holds water and chemicals. High porosity means a raised, damaged cuticle: it soaks product up fast and processes quickly and unevenly. Low porosity is resistant and needs more time.
On Straightment Permanent: the deciding factor. High porosity means it processes fast and unevenly — and on this treatment that is how hair is destroyed rather than merely disappointed.
Bounce (elasticity)
The ability to stretch and spring back, governed almost entirely by disulfide bond health. You can impose a shape on almost any hair. You cannot impose bounce — it has to be earned from healthy bonds.
On Straightment Permanent: removed by design. You are trading spring for straight, permanently, on every hair treated.
Reduction and neutralisation
The two-step chemistry of any perm or relaxer. Reduction breaks the bonds so the hair can be reshaped; neutralisation reforms them in the new shape and locks it in.
On Straightment Permanent: both, in full. Reduction opens the bonds, the iron sets the shape, neutralisation locks it. This is the step most often hurried elsewhere and the reason permanent straightening has the reputation it does.
Processing time
Timed to the hair, not to a clock on the wall. Porosity, texture and history all change how fast a treatment develops.
On Straightment Permanent: three hours on short hair, up to six on thick extra-long. It cannot be rushed.
Read further
Where this sits in the wider family
The free guides covering each tradition — what is in them, where they came from and who they suit.
Keratin & protein family
Every semi and demi-permanent smoothing treatment that coats and fills the hair rather than permanently restructuring it.
Open the guide →Brazilian & plastia
Nanoplastia, taninoplastia and their siblings — built on organic acids rather than aldehydes.
Open the guide →Japanese & Chinese systems
Shukumo kyosei, permanent thermal reconditioning, and the acid-heat systems built for damaged hair.
Open the guide →Rebonding family
Asia's structural straightening tiers, up to permanent pin-straight.
Open the guide →Korean systems
Magic straight, down perm, and the approach that straightens while keeping root lift.
Open the guide →The complete guide
Every smoothing and straightening treatment sold anywhere in the world, in one place.
Start here →Questions people actually ask
Is it really permanent?
On the hair I treat, yes — completely. What is not permanent is your head, because it keeps growing. New growth arrives with your natural curl, and somewhere between three and eighteen months the roots need doing — the range is that wide because growth rate and curl pattern differ enormously.
Will there be a line where it grows out?
Yes. This is the honest difference between this and Straightment Demi, which fades softly with no line at all. If a visible demarcation would bother you, Demi is the better treatment and I will say so.
Can I go back to curly afterwards?
Not on the treated hair. You grow it out by cutting it off. If you change your mind often between straight and curly, this is the wrong treatment for you — genuinely.
Does it damage my hair?
It restructures it, which costs the hair something — anyone who tells you otherwise is selling. Done on strong hair at the right strength, the result is straight, shiny and healthy for years. Done on hair that cannot take it, it is the most damaging thing in this trade. That judgement is what you are paying me for.
Why is it so much more expensive?
Three to six hours of one person’s undivided attention, and a process with no margin for error. It is also the only one you will not be repeating in full — after the first time you are paying roots-and-refresh prices.
Can I have it if I have had a relaxer before?
Tell me first, always. Hydroxide relaxer followed by this chemistry can dissolve hair. It is not automatically a no, but it is automatically a conversation.
Is it safe if I am pregnant or breastfeeding?
That is not my decision to make for you. I will give you the full ingredient list for the exact product I would use, so you can put it in front of your midwife, GP or pharmacist and decide with someone qualified.
How do I know I actually want this?
Start lighter. A good number of people who ask for permanent straightening are happier with Demi once they have lived with it — it gives them the manageability they were actually after, without the commitment or the line.
Real prices, published.
Four questions about your hair and the calculator gives you the exact price for your length and texture, and the appointment to book. No “from” prices that grow once you are in the chair.
See prices & bookAll Down treatmentsNot sure this is the right one? A mini consultation online is £9.95 — refunded against your treatment if you book within 30 days.