Your hair is frizzy because its outer layer is lifted and the inside is dry, so it takes moisture out of the air instead of holding its own. Every other cause on this page is really a cause of that one thing.
Which is why a stronger smoothing product is rarely the fix. What works is putting moisture in before the hair goes looking for it, then keeping the outer layer flat while it dries.
The rest of this post is the specific versions of the question, because the answer changes depending on when your frizz turns up.
What frizz actually is
A hair is covered in overlapping scales, laid like roof tiles. On smooth hair they sit flat, light bounces off them in one direction and the hair reads as shiny. When those scales lift, the hair loses water more easily, takes water in more easily, and stops reflecting light evenly.
Frizz is the visible version of that. Individual hairs swell at different rates, stop lying with their neighbours, and stand away from the rest.
So anything that lifts the scales causes frizz: heat, bleach, hard water, rubbing with a towel, brushing dry, and washing more often than the hair needs. Anything that puts water in the air speeds it up, which is why humidity gets the blame it does.
Why is my hair frizzy after washing?
Because that is the moment your hair holds the most water and the least protection.
Wet hair is swollen and its scales are at their most open, so what you do in the twenty minutes after the shower decides how it dries. Three habits do most of the damage in that window.
Rubbing it with a bath towel. Terry towelling catches the lifted scales and roughs them up further. A microfibre towel or an old cotton t-shirt squeezes the water out instead of dragging it out.
Combing it with nothing in it. Hair is at its weakest wet. A comb through bare wet hair snaps it. A comb through wet hair loaded with conditioner or a leave-in slides.
Letting it dry with nothing on it. Nothing on it means nothing holding the water in, so it evaporates and the hair starts looking for more.
The single change that fixes most after-wash frizz is putting a leave-in on while the hair is still properly wet, rather than after it has dried and disappointed you.
Why is my hair frizzy in humidity?
Because damp air is a supply of exactly what your hair is short of, and hair will take it.
Dry hair pulls water vapour out of the air, swells unevenly, and lifts its scales further to let more in. That is why hair can look fine indoors and change within ten minutes outside, and why the same routine behaves differently in August than in February.
Hair that is already holding enough moisture has far less reason to do this. That is the part people find backwards: the answer to humidity frizz is a more moisturising routine, not a drier one. A leave-in does two jobs at once here, putting water into the hair and leaving a light film that slows the exchange with the air.
The same applies on holiday. If you are going somewhere humid, the thing to pack is the leave-in you already use at home, and use more of it rather than less.
Why is my hair frizzy at the top of my head?
Because the crown takes more wear than any other part of your hair, and much of what stands up there is breakage rather than frizz.
The crown is where a ponytail pulls, where a hair tie sits, where a brush starts, where the sun lands and where a hat rubs. It is also where regrowth is newest and shortest.
You can tell the two apart by looking. Frizz is full length hair standing away from the rest. Breakage is short hairs of roughly even length standing straight up, and no leave-in will lie those down, because they are the right length for a broken hair growing back. They need time and less pulling.
What helps: fabric scrunchies instead of bands with a metal clasp, moving where you tie it rather than using the same spot every day, a silk or satin pillowcase, and not brushing from the crown downwards on dry hair.
Why is my hair frizzy after straightening or blow drying?
Because straighteners and tongs run at temperatures that damage hair structurally, and no conditioner reverses that afterwards.
The frizz that appears a few weeks into daily straightening is not the styling failing on the day. It is the last few weeks of damage becoming visible, and the reason it reads as frizz is that damaged hair holds its scales open permanently.
Two things help, and neither is a smoothing serum. Use a heat protectant every single time, not on the days you remember. And turn the temperature down, because most people straighten hotter than their hair needs.
There is a separate, quicker version of this. If hair goes frizzy immediately after straightening rather than over weeks, it usually was not fully dry when the irons went on. Water trapped under a hot plate turns to steam and lifts the scales on its way out.
Why has my hair gone frizzy all of a sudden?
Because something around it changed, and more often than not it is the water.
Hard water carries dissolved minerals that settle on the hair and stop conditioner reaching it, so hair reads as dry however much you put on. It is the commonest reason a routine that worked for years stops working without you changing anything. London, the South East and East Anglia are hard. A house move, a new area, even a new shower can do it, and so can a holiday somewhere with different water.
There is a full guide to hard water and hair, including how to check yours without a test kit. Read that before you buy another leave-in, because if hard water is your cause, the leave-in is not going to reach the hair.
Other sudden causes worth ruling out: a new shampoo that strips harder than the old one, swimming more often, washing more often, central heating coming on for the winter, and a new set of layers, because a shorter top layer puts more ends on the surface where you can see them.
Hair also changes over a lifetime. Grey and greying hair is often coarser and drier than the hair it replaced, and it frizzes more readily. That is not damage and there is nothing to repair. It is different hair, and it wants a more moisturising routine than the one you had before.
What does not work
Washing it more to calm it down. Every wash costs moisture. More washes means drier hair, which means more frizz.
Brushing it out when dry. Brushing dry hair separates the strands that were holding each other flat and roughs up the scales while it does it. On wavy and curly hair it takes the pattern out and leaves the frizz behind.
A serum on dry hair, on its own. It coats what is already there, so it looks better for an afternoon. It puts nothing back in. Serum after a leave-in is a finish. Serum instead of a leave-in is a cover.
Reaching for the heaviest product on the shelf. Weight is not strength. Fine hair flattened by a cream is not moisturised, it is loaded, and it usually gets washed more often as a result, which makes the frizz worse.
A cold rinse as the whole plan. Lukewarm rather than scalding is the part that matters. A cold blast at the end is not going to undo a hot wash and a rough towel.
Waiting for an anti frizz shampoo to do it alone. A shampoo is in contact with your hair for about a minute and then goes down the drain. The step that lasts is the one you do not rinse out.
What does work, in the order to do it
- Wash in lukewarm water, and only as often as your hair actually needs. For most people that is two or three times a week rather than daily.
- Condition the mid-lengths and ends every wash. Skipping conditioner is the most common cause of frizz I hear about.
- Squeeze the water out with a microfibre towel or a cotton t-shirt. Do not rub.
- Put a leave-in on while the hair is still wet, before it has started to dry. This is the step that decides the result.
- Comb it through with a wide tooth comb while the leave-in is in, from the ends upwards.
- Dry it on a lower heat, or let it dry on its own, and leave it alone while it does. Touching hair as it dries is what breaks the surface up.
- Use a heat protectant before any iron or tong, every time.
- Sleep on silk or satin, or plait it loosely, so the night is not undoing the day.
The bottles we stock for frizz, and which is which
All of these are milk_shake. We are an authorised UK stockist, so they are the same bottles a salon buys. Prices are today's.
Leave In Conditioner, £23.25 for 350ml. The everyday one, and the one to start with if you are only buying a single thing. A detangling spray built on the milk proteins the brand is named for. It goes on wet hair, it is not rinsed, and it is the cheapest way to stop breakage on the way through with a comb.
Whipped Cream Leave-in Foam, £23.25 for 200ml, or £9.83 for 50ml. The same milk protein idea in foam form, for hair that creams weigh down. It spreads further and sits lighter, so this is the fine hair pick. The 50ml is worth having as the one to try first or the one to take away.
Flower Fragrance Incredible Milk, £23.25 for 150ml. The all rounder. A leave-in spray that detangles, controls frizz and protects while you dry, in one step before the hairdryer. It is the vegan edition, built on soy protein rather than milk, and the floral scent stays in the hair. If you would rather the scent did not, the original Incredible Milk does the same job at the same price, £23.25 for 150ml, on milk protein and murumuru butter instead.
Curl Passion Leave-in Conditioner, £23.25 for 300ml. The one for curls and waves. It is weightless, which is what lets you use it every wash without the build-up that flattens a curl pattern by day three. A smoothing product built to flatten will take your pattern out along with the frizz, and this one will not.
Moisture & More Whipped Cream, £22.95 for 200ml. A leave-in foam with hyaluronic acid, for hair that is dry rather than damaged. Different sizes of the molecule sit at different depths, so some of it holds water at the surface and some further in. Also light, so fine hair copes with it.
Thermo Protector, £24.95 for 200ml. The heat protectant, and the only step in a routine that prevents damage rather than treating it. It is an ultra fine spray, which matters more than it sounds: a heavy protector leaves hair sticky and gets skipped, and a protector that gets skipped is worth nothing.
INSTA.LOTION, £29.15 for 250ml. The bad day one. An instant conditioning lotion for hair that needs help now rather than over a routine. Check availability and the current dispatch date on the product page.
Deep Detox Shampoo, £20.84 for 300ml. Not an anti frizz product, and the one to buy first if you are in a hard water area. It lifts the mineral deposit that a normal wash leaves behind, used every three to four weeks in place of your usual shampoo. Check availability and the current dispatch date on the product page.
The whole shelf sits together in Frizz Control if you want to see it side by side.
Frizzy hair questions
Can you get rid of frizzy hair permanently?
Not from a bottle. Salons do smoothing treatments that last for months, and those are a salon job with a salon conversation behind them. We do not sell one. What a routine can do is keep the hair moisturised enough that frizz stops being the default, which in practice is the difference between managing it daily and not thinking about it.
How do I stop frizzy hair naturally, without buying anything?
Wash less often, wash cooler, stop rubbing it with a towel, stop brushing it dry, and leave it alone while it dries. Those five cost nothing and between them they are most of the answer. The products are for the gap that is left.
Why is my hair frizzy when it is wet?
Wet hair with its scales lifted looks rough and feels rough, and on curly hair it also separates as the water weighs it down. It is telling you the surface is open, which is useful: that is the moment the leave-in goes on, not later.
Does frizz mean my hair is damaged?
Not on its own. Dry hair frizzes and it is not necessarily damaged. The difference is that dryness is a water problem and damage is structural. If your hair frizzes but does not snap when you brush it, treat it as dry. If it snaps, splits or has stopped holding a style, that is damage, and it needs a different shelf.
Do I need an anti frizz shampoo, or is the conditioner enough?
For mild frizz a conditioner often is enough. For frizz that comes back the moment you step outside, a rinse-out conditioner is doing half the job. The half that lasts is the leave-in.
What works on frizzy curly hair?
The same mechanism, but the product has to hold the pattern rather than flatten it. The Curl Passion line is the one built for curls and waves, and there is a Curly Girl Method guide if you are starting from scratch.
Is frizzy hair different for men?
The hair is not, the routine is. Shorter hair has proportionally more ends sitting on the surface, so the same amount of dryness shows more. A light leave-in on damp hair does the same job, and a small amount goes a long way.
The short version
- Frizz is dry hair taking moisture from the air, so the fix is moisture in, not smoothing on top.
- After washing: squeeze with a t-shirt, and put the leave-in on while it is still wet.
- In humidity: use more leave-in, not less.
- At the crown: short flyaways of even length are breakage, and they need time rather than product.
- After straightening: a heat protectant every time, at a lower temperature.
- Suddenly, for no reason: check your water first.
- Only buying one thing: Leave In Conditioner, £23.25, or Whipped Cream Leave-in Foam, £23.25, if your hair is fine.
If you would rather not pick, a qualified hairdresser we work with will write you a personalised routine, free, with any order. Send your hair details through Ask an Expert, or take the Hair Quiz if you would rather answer questions than write.
Liam Jones, owner, Innate Beauty. I am an authorised milk_shake stockist and not a qualified stylist, so what is here is what I have learned from stocking these lines and reading their technical sheets.
Related reading: Shampoo for hard water in the UK · The Curly Girl Method UK guide · How to fix damaged hair.
General guidance, not tailored to you. If you have a scalp condition or you are losing hair, speak to a doctor or pharmacist.
