Ingredient dictionary

Ceteareth-20

Ceteareth-20 is a mild, water-loving emulsifier made from fatty alcohols that helps oil and water blend into smooth, stable creams and lotions. It is on the label of 33 products in our library. Checked against our library November 6, 2026.

What Ceteareth-20 does

Blends oil and water into one smooth mix
Keeps creams and lotions stable
Helps lift oil and makeup when cleansing
Keeps sunscreen filters evenly mixed

Ceteareth-20 is made by attaching ethylene oxide to cetearyl alcohol, a blend of fatty alcohols that can come from plant oils or synthetic sources. The 20 means that, on average, twenty ethylene oxide units are attached to each molecule. This process, called ethoxylation, makes the molecule water-friendly.

Formulators use it as an emulsifier. Oil and water separate on their own, so a shared partner is needed. Ceteareth-20 has a fatty end that grabs oil and a water-loving end that grabs water, so it holds the two together. It is often paired with cetearyl alcohol to give creams body. The result is a smooth, light texture that spreads easily.

Good for

Suits lotions, sunscreens, shampoos and makeup removers, including gentle formulas for babies.

Frequently asked questions

Is Ceteareth-20 safe for babies?

Ceteareth-20 shows up in many baby lotions because it is generally mild and helps creams stay smooth. Like any surfactant, it can bother skin that is already sensitive, so patch testing new products is a sensible habit. If your baby has a skin concern, check with a pediatrician.

Does Ceteareth-20 protect against the sun?

No. Ceteareth-20 is not a sun filter. In sunscreens it helps keep oil-soluble filters evenly mixed into the water-based formula, so the layer on skin stays uniform. Protection comes from the filters listed on the label, so check the active ingredients and reapply as directed.