What is Ceteareth-20?
Ceteareth-20 is an emulsifier that helps oil and water mix. A widely used emulsifier rated around 2 on classic lists; INCIDecoder places it at 2.
You may see it on labels as Ceteareth-20, Ceteareth 20, so it can hide under more than one name in an ingredient list.
Where Ceteareth-20 shows up
You'll most often find Ceteareth-20 in almost any lotion or cream, where it keeps the oil and water phases blended. Separately from clogging, its irritancy is rated 0/5 — low, so it's unlikely to sting or sensitise on its own.
Is Ceteareth-20 bad for acne-prone skin?
That low score makes Ceteareth-20 a reasonable choice even for acne-prone skin. As always, individual reactions vary, but it is not a likely cause of clogged pores.
Worth flagging: Ceteareth-20's rating is disputed. Credible sources land on different numbers, which is why we show a range rather than a single score — and why your own experience is the best tiebreaker.
Note for fungal-acne (malassezia) sufferers: Ceteareth-20 is commonly avoided in fungal-acne routines, since it falls into the fatty-acid or ester families the yeast can feed on. The evidence there is looser than for comedogenicity — see our fungal-acne checker for context.