Deodorant vs antiperspirant: what the ingredients show

Two products, two jobs

Sweat starts out odourless. The smell comes from skin bacteria breaking down its components, and the warm, moist underarm suits them well.¹ The two products work on different ends of that. In the EU's ingredient database, the antiperspirant function is "reducing perspiration", while the deodorant function is reducing or eliminating unpleasant odour.² EU claims guidance calls them different products with different functions, and says comparing an antiperspirant's effect on wetness with a deodorant's is unfair.³ Many products do both jobs and are sold as deodorant-antiperspirants.¹

Antiperspirants: aluminium salts

Antiperspirants rely on aluminium salts, which are thought to form a gel plug in the sweat duct that keeps sweat from reaching the skin.¹ US rules list 18 permitted antiperspirant actives, all aluminium compounds, each with a maximum: 25% for salts such as aluminium chlorohydrate and aluminium sesquichlorohydrate, 20% for the aluminium zirconium salts, and 15% for aluminium chloride in a water-based, non-aerosol product.⁴

Ingredient names keep the American spelling, Aluminum, on EU labels too. CosIng lists Aluminum Chlorohydrate, Aluminum Sesquichlorohydrate and Aluminum Zirconium Tetrachlorohydrex Gly with antiperspirant, astringent and deodorant functions.⁵⁶⁷ EU law limits them in two Annex III entries:

• Aluminium zirconium chloride hydroxide complexes, glycine complexes included (Annex III, entry 50): antiperspirants only, at most 20% as the anhydrous complex and 5.4% as zirconium, not in aerosol sprays, and labelled "Do not apply to irritated or damaged skin".⁸
• Other aluminium-containing ingredients (Annex III, entry 381), added by Regulation (EU) 2026/909: at most 7.73% aluminium in non-aerosol antiperspirants or deodorants and 3.24% in aerosols. Products that do not comply may not be placed on the EU market from 1 January 2027, or made available from 1 July 2028.⁸⁹

Those limits reflect a 2024 opinion of the EU's Scientific Committee on Consumer Safety.⁹ The committee concluded that aluminium compounds are safe in non-spray products at the maximum levels it set, and in sprays at those levels provided fine particles stay below a set share. It also noted that combined exposure from cosmetics and food may exceed safe limits for consumers at the highest exposure levels.¹⁰ A label gives no concentrations, so it cannot show how close a product comes to any of these limits.

Deodorants: antimicrobials, fragrance and absorbers

A 2023 review describes three kinds of deodorant ingredient: antimicrobial agents that slow the growth of odour-forming bacteria, fragrance that masks odour, and odour absorbers.¹ On a label they look like this:

• Antimicrobials. The review's examples include triclosan, propylene glycol and ethylhexylglycerin.¹ Ethylhexylglycerin carries a deodorant function in CosIng¹¹, and triclosan is on the EU list of permitted preservatives, at up to 0.3% in certain products, non-spray deodorants among them (Annex V, entry 25).⁸
• Odour absorbers and other deodorant ingredients. The review names sodium bicarbonate as an odour absorber.¹ Sodium Bicarbonate, Zinc Ricinoleate and Triethyl Citrate all carry a deodorant function in CosIng.¹²¹³¹⁴
• Fragrance. Parfum, and named fragrance substances such as limonene, linalool, eugenol and geraniol, which the review lists among common odour-masking ingredients.¹ Farnesol has deodorant and perfuming functions in CosIng¹⁵, and EU labels must name it above set levels (Annex III, entry 82).⁸ See EU fragrance allergen labels.
• Alcohol. Alcohol Denat. carries antimicrobial and solvent functions in CosIng¹⁶, and the review names ethanol as a common carrier in antiperspirants.¹ Alcohol denat. in skincare explains the names.

Telling them apart on a label

In the US, a deodorant is a cosmetic, while a deodorant that is also an antiperspirant is both a cosmetic and a drug and must meet the rules for both.¹⁷ So an antiperspirant carries a Drug Facts box naming the active ingredient, its strength and its purpose¹⁸, a use such as "reduces underarm wetness", and warnings including "Do not use on broken skin" and "Ask a doctor before use if you have kidney disease".⁴ The cosmetic ingredients follow as inactive ingredients.¹⁷

In the EU both are cosmetics, so there is no Drug Facts box: the aluminium salt sits in the one ingredient list, which runs in descending order of weight down to 1%. The pack must also state the product's function unless its presentation makes that clear (Article 19).⁸

"Aluminium free" and other claims

Every antiperspirant active the US rules allow is an aluminium compound⁴, so an aluminium-free product is not an antiperspirant there. In the EU, "free from aluminium" is a free-from claim: in the Commission's 2016 report, ten Member States had flagged claims such as "free from parabens" or "free from aluminium" as unfair because they denigrate legally authorised ingredients.¹⁹ What clean beauty means explains how EU guidance treats free-from claims. On a US label, "alcohol" on its own means ethyl alcohol, and a product called alcohol free may still contain fatty alcohols.²⁰

What to look for on the label

• An aluminium salt, such as Aluminum Chlorohydrate or an Aluminum Zirconium name, marks an antiperspirant or a deodorant-antiperspirant.
• A Drug Facts box on a US pack, with the salt as the active ingredient and its percentage.
• The EU warning "Do not apply to irritated or damaged skin" with an aluminium zirconium salt.
• Parfum and named fragrance allergens on either kind, if you avoid fragrance.

The ingredient checker shows what each ingredient in a deodorant or antiperspirant does, and marks fragrance and named fragrance allergens. No list gives concentrations, so neither the label nor the checker can show how a product compares with the legal limits.