Why do salons wash your hair before coloring?

Author: Mr. Conner Thompson DVM  |  Last update: Friday, November 7, 2025

In most cases, having freshly washed strands is ideal—as Moore says, “hair color needs the path of least resistance” for the most seamless end results. This is especially true if you're using a semi-permanent hair color, like a hair gloss.

Why do hairdressers wash hair before dying?

Washing your hair ensures that it is free from any product buildup, dirt, or oils that may interfere with the color application process (3). - Clean hair allows the colorist to have a clear canvas to work with, making it easier to achieve the desired color result (3).

What happens if I don't wash my hair before dying it?

When the hair is not clean it's your hair, time, and wallet that suffers. Many chemical reaction possibilities and an overall decrease in colour/bleach effectiveness are major factors. Extra damage can be incurred which is the most unfortunate.

Is it better to color hair clean or dirty?

That said, on the flip side if you have too much oil or dirt, it can prevent the color from working as well and efficiently. For this reason, we recommend coming with clean hair that was washed either the night before or morning of to allow your scalp to have some natural oils, but not be dirty.

Do hairdressers prefer clean or dirty hair?

It's generally acceptable to go to the hair salon with dirty hair. Many stylists prefer that clients come in with unwashed hair, especially for certain services like cutting or coloring, as natural oils can help protect the scalp and hair.

How to Prep for Safely Coloring/Dyeing Natural Hair at Home or Pre Salon Visit | ~Smooches~💋

Should I wash my hair before going to the salon for color?

Timing Your Wash: If you're going for hair coloring, it's often recommended to wash your hair 24 to 48 hours before your appointment. This allows your scalp's natural oils to protect your skin during the coloring process.

How much to tip a hairdresser?

A 20% tip may be standard, but the percentage can vary. More complex jobs or a stylist that went above and beyond might merit a bigger tip. If service was poor, a little less might be appropriate.

What not to do before dying hair?

Along with washing your hair right before dyeing it, avoid applying any styling products, like dry shampoo or leave-in conditioners.

How long to leave hair dye in for grey hair?

Processing time with grey hair

The pigments in the dye need more time to penetrate through that so they can do their job. So with grey hair it's also best to let the dye sit for 45 minutes from the moment you've finished applying all of the dye so you'll be sure you have enough coverage.

Should I wet my hair before dying it?

"Semi-permanent and demi-permanent hair color can be applied to wet or dry hair, but wet hair application in not recommended for permanent hair color." Meanwhile, permanent color changes require a dry hair application. This could mean going lighter, or darker.

How soon after washing hair can I dye it?

It's best to avoid washing at least 24 hours before dyeing. However, if your hair is really dirty, has a lot of product in it, or you need to shampoo for a special occasion, you can do that – as long as it's a one-off, you shouldn't see any long-term negative effects.

Can hair be too greasy to bleach?

Stylists advise that bleach does not need to go on clean hair, and that it's actually healthier for your hair to be a little oily when you bleach.

How to prep hair before coloring?

You generally shouldn't shampoo immediately before coloring, because this will remove the natural oils that help protect your scalp during the coloring process. It's best to shampoo 12 - 24 hours before coloring when using semi-permanent or demi-permanent hair color. Shampoo 24 hours before using permanent color.

Can I dye my hair if I haven't washed it in 3 days?

As mentioned, your hair type can play a role, too. Those with oily hair may only need to wait one day between their last shampoo and next dye job. People with dry hair, meanwhile, may need 2-3 days in between to allow enough oil to build up.

How clean should hair be before Colouring?

The day before should leave oil-prone hair and scalps fresh enough for flawless application. Meanwhile, for normal or dry hair types that aren't as prone to oiliness, 'day two' or 'day three' hair can act as the perfect base for applying hair color.

Why do salons wash your hair after coloring it?

A thorough rinse after the coloring process ensures the removal of any excess chemicals from your hair. This not only prevents potential damage but also encourages the bonding process between the new color and your hair shafts.

Is it better to go lighter or darker to cover gray hair?

Pick a lighter hair colour

A lighter colour will then look better. Your hair follicles produce less pigment as you're turning older. If there's no more pigment being produced in the hair follicles, your hair turns pigmentless.

Is box dye bad for your hair?

Yes, box dye can be damaging due to the harsh chemicals and improper application methods.

Should I dye my roots or ends first?

Apply color to your roots first. Hair that's been previously colored is porous and soaks up color easily, but new growth requires more processing time. Leave color on your roots for the full time and only process ends for half the required time. It'll give you a nice even color from root to tip.

Do hair stylists prefer clean or dirty hair for coloring?

“There was a time when hair color was very harsh and you needed a barrier between it and your skin,” she says. That's not the case anymore: Today, hairstylists generally prefer the hair to be clean before dyeing it.

What not to do before going to hair salon?

Having your hair too clean when you go to the salon is not the best idea. On the other hand, hair with too much oil and products is not safe for hair health. Don't use too many hair products such as styling gels or mousses on the same day you want to get your hair done. This could make your hair color look uneven.

Is a $5 tip good for a $20 haircut?

“$10 to $20 is generous,” Rivera said. “Most people will do $5.” Others said people should leave a similar tip to what they would leave at a restaurant. “I would say around 20% is fine,” said Adam Quintero, owner of Up Hair in the Castro.

Is it bad to not tip your hairdresser?

A great way to determine if a tip is the “norm” for a hairstylist is by the way they charge. Most salon professionals who charge by the hour, not by the service are no-tip salons. If you are charged by the service, it is generally customary to tip. Tipping is always appreciated but never expected!

Previous article
Does biotin affect hair color?
Next article
Does short hair make you attractive?