PEG-40 Stearate
Reviewed by Emma · Last updated 18 Aug 2026
Also known as: Stearic Acid
Typically functions as a cleansing agent in skin care formulas | Can also be used as a thickener/texture enhancer or to help keep ingredients soluble
Addresses
EWG Safety Score
What Is PEG-40 Stearate?
PEG-40 stearate typically functions as a cleansing agent in skin care formulas, but it can also be used as a thickener/texture enhancer or to help keep ingredients soluble. You can find this ingredient in all kinds of skin care products including cleansers, creams, exfoliants, and serums.
Researchers have also successfully experimented with using PEG-40 stearate to increase the topical penetration of key ingredients in medicinal settings. “PEG” is short for polyethylene glycol, which is currently used in many liquid pharmaceuticals.
PEG-40 stearate has a long history of cosmetic use and has passed safety assessments conducted by groups such as the Cosmetic Ingredient Review (CIR) over the years. In 2005, the CIR Expert Panel reaffirmed PEG-40 stearate’s safety (their report looked at products containing 0.07-7% of this ingredient). Higher amounts of this stearate have humectant (moisture-binding) properties.
Clinical Evidence & References
Published Research
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Food Biophysics, July 2020, pages 40–47 [URL not available]
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International Journal of Toxicology, 2005, pages 1–102 [URL not available]
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Journal of Pharmacy and Pharmacology: An International Journal of Pharmaceutical Science, July 2003, pages 911-919 [URL not available]
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Journal of the American Journal of Toxicology, November 1983, pages 17–33 [URL not available]
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PEG-40 Stearate is a variant of PEG-100 Stearate, the form you will most often see on an ingredients list.
Multitasking ingredient that can be used as an emulsifier/cleansing agent in cosmetic formulas | May also be utilized to deliver a soft, moisturised feel to skin, thanks to its emollient properties
Related Ingredients
PEG-100 Stearate
Multitasking ingredient that can be used as an emulsifier/cleansing agent in cosmetic formulas | May also be utilized to deliver a soft, moisturised feel to skin, thanks to its emollient properties
PEG-75 Stearate
A surfactant that helps stabilise and blend formulations, commonly used in sunscreens and cleansers
PEG-30 Stearate
Made from polyethylene glycol and stearic acid | Has cleansing, emulsifying, suspending, and solubolizing properties
PEG-8 Stearate
A surfactant and emulsifier that helps blend oil and water-based ingredients
PEG-20 Stearate
A synthetic emulsifier that helps bind water and oil in skincare formulations
PEG-35 Castor Oil
A synthetic emulsifier derived from castor oil, used to blend oil and water in formulations
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