At under a tenner a box, home hair colour is cheap but let’s dispel any notion that it’s nasty. The latest permanent hair dyes are so close now to premium salon formulas, nobody would ever guess you’d not been for a pricey professional colour – unless they checked your bank account.
What you really pay for at the salon is professional expertise, from making the right hair colour choice to applying the dye seamlessly, but it’s perfectly possible to replicate those things at home. Trust me on this one: I might be a beauty director with access to the UK’s top colourists but I dye my own grey roots at home about 90 percent of the time. Has anyone ever spotted the difference? No, they have not.
If you, too, would like to know how to get expensive-looking hair at home, just follow this expert advice on everything from prep to techniques and the best conditioning and bond strengthening aftercare. At the end you'll also find a buyer's guide to the best home hair colours, packed with smart, salon-inspired technology for healthy, glossy, vibrant results any pro would be proud of.
How to prep your hair before dyeing it
The healthier your hair is before you colour it, the better your results will be. “Use an intensive mask ahead of colouring,” advises Josh Wood, celebrity colourist and founder of an eponymous home hair colour range. “If the fibre of your hair is well hydrated, it’s more able to absorb the dye, which means a more even, luxurious-looking result.”
Percy & Reed Bye Bye Dry Hydrating TLC Mask was the best hydrating hair mask in the latest Good Housekeeping Institute tests, scoring a mighty 90/100. Our testers loved how it made their hair intensely nourished, smoother, less frizzy and shinier.
However, don’t dye your hair when it’s freshly washed. “The optimal time to dye your hair is two days after you’ve washed it,” says Michael Douglas, celebrity hair stylist, mdLondon founder and Garnier ambassador. “This allows the acid mantle on the scalp to build up, protecting against irritation from colouring. Don’t worry about product residue on your hair affecting the result. Permanent dye has no problem penetrating through dry shampoo, serums, hairspray or even oils.”
How to choose the right hair dye colour
Rule no1: if you want a big colour change, it’s safer to pay a professional. “If you’re colouring your own hair, staying within one shade of your existing colour is the safest option, says Michael. “You can still make a nice visible difference just by changing the tone, making it warmer or cooler. If you’re staying the same depth or going darker, you can use a semi-permanent (which washes out gradually over around 20 washes) unless you have greys to cover. These should fade evenly and will not leave you with a harsh root line."
In GHI testing, L'Oreal Paris Casting Crème Gloss was the best semi-permanent hair dye, thanks to its ultra-conditioning formula and rich results.
The biggest mistake people make when colouring their own hair is going too dark with a permanent dye, Michael adds. “It’s easy to darken hair, but it’s very hard to get rid of it when it ends up looking harsh against your skin tone. You’ll need to go to a salon to get the colour stripped out. So if you’re deciding between two shades at home, always go for the lighter one. If it's not dark enough, then you can then put the darker one on. What you can't do is the opposite of that; it won’t work.”
The ‘what result to expect’ photos on the back of the box are helpful, but you need to take your hair history into account. “The guide photos are a very good indicator of the result you can expect on healthy, virgin (uncoloured) hair," Michael explains. "Problems with results against expectations mostly arise when products are used on hair that has been previously coloured or is dry, damaged and porous, without the current colour and condition being considered."
Likewise, virtual AI-powered try-on services can be a useful, fun way of seeing which colours suits you, but don’t take them too literally. If in doubt, most hair dye companies offer a consultation to help you make the right choice.
How to cover greys
"If you want to cover grey hair completely, or want to lighten your natural hair colour for that matter, then you will need permanent colour," Michael explains. "With semi-permanent colour, you can stay the same depth, go darker and cover 50% grey. It is not possible to lighten your natural colour with a semi-permanent product."
A permanent dye does come with commitment. "It will deliver 100% grey coverage but a root line will appear as your hair grows," says Michael. Find our full guide to colouring greys at home here
Remember the patch test
Always do a patch test before dyeing your hair. Michael explains: "A patch test is important as it may help determine whether you might get an allergic reaction to the colour. Reactions are rare but you can develop a new allergy at any time, therefore it is necessary to do a patch test 48 hours before you colour each time."
You might also wish to consider doing a strand test. "A strand test is helpful to see how the colour will develop on your hair and from this you can make a judgement call on whether you’ll like it or not before committing to all over colour," he explains.
"It is worth considering that plenty of factors can affect the finished result such as texture and the condition of the hair."
Remember to do your strand test somewhere discreet, not on the top of your hair or anywhere around your hair line.
Follow the hair dye instructions
It may sound obvious, but reading the hair dye instructions is absolutely crucial, says Michael. "There is no point taking any risks by winging it. All colour brands have slightly different formulas, so please make sure you read the instruction leaflet, which will give details on application and development times. This is key to helping you achieve the colour result you would like."
Pick the right tools
The tools you use when applying home hair colour comes down to personal preference. Hairdressers swear by a tint bowl and brush but some people find it easiest to just apply dye straight from the nozzle. Dark clothes and towels are a must, and make sure you have some Vaseline to help avoid staining. "Apply a small amount around the hairline, on the forehead and temple area," advises Michael. "Avoid getting it on the hair itself as it forms a barrier to colour but it’s helpful to stop staining on the skin around the hairline."
How to apply hair dye
No surprises here, but application is key. "The better the application, the better the result," says Michael "For example, if you have long or very thick hair and you think you will need two boxes, then use two."
Wondering where to start your application? "The best place to begin is with the areas you can see, the parting, hair line and the areas where you have most greys," he adds. "If you are simply refreshing your roots, try not to overlap the colour you are applying to the previously coloured hair to ensure an even and seamless finish."
Stretching out the time between root retouches with one of the best instant root cover-ups will really help to avoid overlapping, which can cause bands of uneven colour.
For a premium root retouch, a great tip from Josh is to apply a semi-permanent gloss on your lengths while you're doing your greys. (His own formula is excellent.)
“It’s similar to what we do in the salon, using a separate product to refresh the colour and add shine. Either use a coloured gloss or a correcting product to tone down any brassiness. It creates a glossier, premium look.” Find our full guide to colouring grey roots at home here
What to do if your hair colour goes wrong
- If it’s too dark...
"If you’ve used a semi-permanent colour then wash it a few times with an anti-dandruff shampoo," says Michael. "Leave the shampoo in for 5 minutes before rinsing to help remove some of the colour and lighten the hair. For permanent colour that is too dark, a trip to the salon is your best bet."
- If it's too light...
"This is an easier fix," adds Michael. "To darken slightly is straightforward because almost all hair dye colours use a universal numbering system – the higher the number, the lighter the colour. If the depth of 7 is too light, then apply a 6 over the top. You can use a semi-permanent to darken the hair with minimal damage."
How to care for your hair after you've dyed it
Conditioning is key. Michael says: "You will usually get a conditioning treatment with your home hair colour so make sure you put it to good use! Then include a weekly hydrating mask into your routine." Adding in one of the best bond building treatments will also keep your hair strong. Using a colour glossing treatment is a great way to elevate your home hair dye finish, and keep the colour fresh between touch-ups.
The best permanent box dyes for a salon finish
For fresh, vibrant colour without compromising on condition these are the pro-inspired new hair dyes to try
Not only is this created by one of the UK’s best colourists, it's also the winner of GHI's best home hair colour . Not only is the result nicely multi-dimensional, there's a barrier cream, stain-removing wipe and deep treatment in the box.
This dye has a built-in conditioning technology called HaptIQ, which creates strengthening bonds within your hair while you colour it. It promises to leave hair vibrant, glossy and more resistant to breakage, and was a joint winner in GHI's testing.
A great, easy-to-use formula with an excellent post-colour conditioner. The grey coverage is excellent without ever looking blocky. Plus, it’s almost always on a deal somewhere, making it even more of a bargain.
The matching Root Touch Up product is an all-time GH favourite, and we like to switch between these two, depending on how much time to dedicate to grey root upkeep.
This permanent dye comes with a follow-up mask booster, designed to improve staying power. Used after a month, the booster deposits fresh pigments into hair to restore that shiny, just-coloured look.
John Frieda Precision Foam Colour
GHI testing found this permanent foam dye ultra-easy and non-messy to apply. It spreads quickly and evenly, making it simple to even reach the back of your head. It offers 100% grey coverage, too.
