What Is Ammonia-Free Hair Dye, and How Does It Work?

Ammonia-free hair dyes are a great way to experiment with new hair colors sans the damage. A pro breaks down how to use these versatile formulas.

By Leann Garofolo & Powered By L’Oreal Professional Products Division
Update Date: 16 Feb 2024

What Is Ammonia?

According to the National Institute of Health (NIH), ammonia is a pungent, colorless gas often found in household cleaners and various fertilizers. In hair dye, it helps to lift the hair’s outer cuticle so your dye’s pigment can penetrate deeper into the hair’s cortex. Ammonia is typically the ingredient that distinguishes permanent from non-permanent hair color.

While ammonia effectively creates permanent hair color, it can also be very damaging to the hair shaft. The repeated lifting of your hair's outer cuticle, Bond says, causes it to swell—and over time, hair is less able to recover from that swelling. “The hair can lose elasticity and become stiff, dry, frizzy, and [prone to] breakage.”

The ingredient also has a strong scent that can make the coloring process unpleasant for you and your colorist. If you have a sensitive nose or any known allergies to ammonia, you may already steer clear of the chemical in your hair coloring routine.

What Is Ammonia-Free Hair Dye?

Ammonia-free hair dye is exactly what it sounds like: a dye that doesn’t include ammonia in its formula. There are three main groups of non-ammonia dyes you should know about, which we outline below.

Non-permanent

Temporary and semi-permanent hair dyes fall under the umbrella of non-permanent ammonia-free hair dyes. The pigments in these dyes sit on the hair's surface and don’t require any developing or pre-mixing before application. Bond notes that this category is where you’ll find vivid color sprays, root touch-ups, and colored conditioners, which allow you to temporarily change your hair color without the commitment (or damage). Depending on your chosen formula, these dyes can last anywhere from one day to a week or more.

For fast gray coverage, try one of L’Oréal Professionnel’s Instant Root Fix sprays to temporarily cover your grays until you wash your hair. Or, test the waters with a punchy pop of color using Biolage Professional’s ColorBalm Color Depositing Conditioners. Take your pick from six shades that help refresh, intensify, and enhance your color in just five minutes.

Demi-Permanent

Demi-permanent hair color is the sweet spot between non-permanent and permanent hair color, lasting up to 24 washes. These deposit-only formulas help tone, refresh, and enhance your hue but won’t lift your actual color or remove any existing pigment. They’re a great way to blend grays, camouflage your roots, and extend the life of your color between touch-ups.

Many demi-permanent ranges come in the form of professional hair glosses. Bond says that these dyes usually contain mild alkaline agents like monoethanolamine (MEA), which are added in very low quantities to help slightly open the hair and get color agents inside. “MEA in these small amounts leaves the hair in great condition with shiny results,” she adds.

Permanent

Although we mentioned that most permanent hair dyes contain ammonia, exceptions do exist. Revolutions in professional formulas have made it possible to achieve lasting color sans the notoriously odorous chemical.

“The biggest innovation over the last [decade] has been ammonia-free permanent hair color,” says Bond. These formulas typically offer all the benefits of demi-permanent hair color (like shine and conditioning) but with the ability to lighten hair and fully cover grays.

“As with any new technology, there are very specific directions for application,” says Bond. For this reason, she urges consumers to visit a professional colorist for the best results.

Does Ammonia-Free Hair Dye Cover Gray Hair?

Some, not all, ammonia-free hair dyes have the ability to cover gray hair. According to a 2018 study in the International Journal of Trichology, gray hairs have a different structural makeup than their pigmented counterparts, impacting how well strands absorb and retain artificial color. Therefore, only certain formulas are powerful enough to hide grays completely. We recommend scheduling a consultation with a colorist if you want to bid farewell to your grays. They have access to high-quality formulas that can effectively cover grays while preserving the integrity of your hair.

What Is the Best Hair Dye Without Ammonia?

Your salon will be well-stocked with the latest and greatest ammonia-free hair dyes, but Bond is partial to color transformations using iNOA Hair Color by L’Oréal Professionnel. This line uses a unique oil delivery system in place of ammonia to drive hair color into hair’s fiber.

“iNOA is the original ammonia-free permanent hair color that works just like ammonia-based hair color, only [with] all the benefits of being ammonia-free,” says Bond. “The lift is the same, the deposit is richer and more durable, the shade selection is wider, and the condition of your hair will be as close to virgin hair as physically possible.” Plus, she says that iNOA can cover up to 100% of white hair and doesn’t emit an offensive odor, both major upsides compared to other formulas.

Ammonia-free permanent hair color from iNOA also makes it easy to try the latest hair color trends with less damage. Lean into the mob wife aesthetic by opting for a shade in the Black Abyss collection, which features jet black tones with subtle hints of red, purple, green, or brown. Red hair is another color trend we expect to see throughout 2024. Try your hand at cherry cola with the Nebula line, or experiment with shades of copper and burgundy in the iNOA portfolio until you find the perfect fit.

No matter what color you choose, giving your mane the proper at-home TLC is essential to maintain your gorgeous salon color. Be sure to invest in a shampoo and conditioner specifically made for color-treated hair, like L’Oréal Professionnel Vitamino Color Radiance Shampoo and Conditioner. The resveratrol-infused system hydrates hair and helps protect color against fading for up to eight weeks.*

*Instrumental test shampoo + conditioner.