Found a dusty old box of hair dye? The one that’s lived right at the back of the bathroom cupboard since you-can’t-remember-when? Or maybe you’ve stocked up on a 3 for 2 hair dye deal and stashed a few forgotten boxes away? We’ve been there! But whatever the reason, you need to know, does hair dye expire?
The answer is, technically, NO!
If you look for a ‘Use by’ date, it’s likely you won’t find one on the box. This is because hair dye manufacturers believe that, stored correctly, a sealed hair dye box can last forever. Yippee!
How long do hair dyes last?
When it’s been stored unopened and sealed: Guidance says hair dye can actually last as long as three years!
Up until then, it is considered safe to use – and beyond.
There’s no evidence that using expired hair dye is unsafe, but it might not work as effectively or last as long.
Does hair dye expire after opening it?
When it’s been opened and mixed: Hair dye is designed to be mixed together with the developer and applied to your hair within an hour.
After that, the solution becomes oxidised and the chemicals start to degrade. If you have any hair dye left after the hour is up, it won’t keep (or work) so just throw it away!
Even natural hair dye products that don’t contain chemicals or preservatives will also degrade rapidly after they’re opened, no matter how they’re stored.
Fortunately, permanent hair dye does not go out of date. That means it doesn’t go bad or become ineffective over time.
In fact, the only thing that could happen to a box of permanent dye is that it might lose its potency over time due to exposure to light or heat. That’s why it’s important to store them in a cool place away from direct sunlight and high temperatures.
You should always follow the instructions on the box when applying permanent hair dye.
What will happen if you use expired hair dye?
Using it is not likely to damage your hair by breaking it or making it fall out, but you may not get the colour results you were longing for.
The colour of the dye may come out darker, the dye may smell or you may find there are patches of colour after dyeing your hair because the chemicals have simply aged.
It’s always best to follow the package instructions, but sometimes people are unsure of what they should do.
There are some things you can try when deciding whether or not to use an old product.
For example, if the expiration date is on the bottom of the box and there is no seal over it then it may be okay.
You can also check with your hairdresser about how long an individual product lasts before becoming ineffective.
It’s a sensible idea to do a patch test before you use the hair dye, to test for allergies or any dodgy colour reactions.
Watch and learn: Here’s what happens when you use a 5+ year old hair dye!
Can you keep unused hair dye?
Hair dye is a necessary part of life. It’s how we express ourselves, and it’s an important tool for those who work in the beauty industry.
But with so many brands out there, it can be hard to know which one will work best. And what happens if you don’t use all your hair dye?
Can you keep unused hair dye? The answer is yes! It is possible to store hair dye for up to 3 years in the right conditions.
Just store your unused hair dye in a cool place away from any direct sunlight or heat source as this could affect the quality of the product.
Yes, you can safely use that old box dye you’ve found, whether you bought in ’79 or 2009.
So go ahead and use up those boxes of hair colour sitting in your bathroom cabinet! You won’t have any problems with them going bad on you.
And remember – always follow the instructions for mixing the product before applying it! It will make all the difference when it comes to how well your colour turns out.
You can find out the answers to more common hair dye questions on our FAQs page.