CosmeticBet
Preservatives

Sodium benzoate

INCI: SODIUM BENZOATE

The salt of benzoic acid, an acid found in berries too.

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C7H5NaO2144.10 g/mol
sodiumoxygencarbon
2D drawing from PubChem 517055 (hydrogens hidden)

How common

All products31%
In shower gels77%
In shampoos69%
In conditioners33%

4,539 of 14,784 products with a full ingredient list in Open Beauty Facts; No. 5 of all the names found on their labels.

What it is

  • The sodium salt of benzoic acid. Benzoic acid occurs naturally in many plants: most berries hold around 0.05%.

    3 sourcesHide
    Sodium benzoate is an organic sodium salt resulting from the replacement of the proton from the carboxy group of benzoic acid by a sodium ion.[1] PubChem (US National Library of Medicine) · open source
    Benzoic acid occurs naturally free and bound as benzoic acid esters in many plant and animal species.[1] PubChem (US National Library of Medicine) · open source
    Appreciable amounts have been found in most berries (around 0.05%).[1] PubChem (US National Library of Medicine) · open source

Why it is in products

  • Mostly as a preservative; benzoic acid and its salts are also used as fragrance ingredients. Benzoic acid is a common food preservative too.

    2 sourcesHide
    Benzyl alcohol, benzoic acid and its salts, and benzyl benzoate function mostly as fragrance ingredients/preservatives in cosmetic products.[2] US Cosmetic Ingredient Review expert panel · 2017 · open source
    Benzoic acid is a fungistatic compound that is widely used as a food preservative.[1] PubChem (US National Library of Medicine) · open source

What it does

  • Like other acid preservatives, how well it works depends on the product’s pH, which sets how much of the acid is in the uncharged form that can get into germs.

    Some evidence2 sourcesHide
    pH is considered to be a major determinant of the organic acids’ effectiveness because it affects the concentration of formed undissociated acids[3] Study · 2018 · open source
    Uncharged molecules are those forms that enable the penetration of organic acids into the cell[3] Study · 2018 · open source

Downsides and safety

  • The US expert panel concluded that benzoic acid and its salts are safe as used in cosmetics.

    Well establishedSourceHide
    it was concluded that benzyl alcohol, benzoic acid and its salts, and benzyl benzoate are safe in the present practices of use and concentration described in this safety assessment[2] US Cosmetic Ingredient Review expert panel · 2017 · open source

Where it works

Works insidethe product

It works in the product, keeping germs from growing there.

SourceHide
Preservatives may be used in cosmetics to prevent the growth of harmful bacteria and mold, in order to protect both the products and consumers.[4] US Food and Drug Administration · open source

Rules

European Union

  • Allowed as a preservative up to 2.5% in rinse-off products, 1.7% in oral products such as toothpaste, and 0.5% in leave-on products (counted as the acid).

    SourceHide
    Benzoic acid Sodium Benzoate 65-85-0 532-32-1 200-618-2 208-534-8 Rinse-off products, except oral products 2,5 % (acid) Oral products 1,7 % (acid) Leave-on products 0,5 % (acid)[5] EU law · 2026 · open source

United States

  • Not on the FDA’s list of prohibited or restricted cosmetic ingredients. In the US, cosmetics and their ingredients (other than colour additives) don’t need FDA approval before sale.

    SourceHide
    Under U.S. law, cosmetic products and ingredients, other than color additives, do not need FDA approval before they go on the market[6] US Food and Drug Administration · open source
    We searched the FDA’s list of prohibited and restricted cosmetic ingredients: no entry.open the list

Sources

  1. PubChem: Sodium benzoate (CID 517055), record description PubChem (US National Library of Medicine)PubChem (US National Library of Medicine)
  2. Safety Assessment of Benzyl Alcohol, Benzoic Acid and its Salts, and Benzyl Benzoate International journal of toxicology, 2017US Cosmetic Ingredient Review expert panel
  3. Cosmetics Preservation: A Review on Present Strategies Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry, 2018Study
  4. Parabens in Cosmetics | FDA US Food and Drug Administration
  5. Regulation (EC) No 1223/2009 on cosmetic products, consolidated text of 18 May 2026 Publications Office of the European Union (EUR-Lex/Cellar), 2026EU law
  6. Prohibited & Restricted Ingredients in Cosmetics | FDA US Food and Drug Administration

Checked against these sources on 4 November 2026. Spot a mistake? Tell us.