Ingredient review

Bis-Stearoxydimethylsilane

INCI: BIS-STEAROXYDIMETHYLSILANE

A gentle silicone ingredient that leaves skin feeling silky smooth without clogging pores.

beautyskincarehaircareemollient

In plain English

Bis-Stearoxydimethylsilane is a type of silicone that spreads easily on the skin and forms a light, breathable film. It helps products feel silky and smooth, reduces tackiness, and can improve the texture of creams and lotions. Because it's non-greasy and low-risk for irritation, it's commonly used in moisturizers, sunscreens, and makeup primers.

Review score

Safety, usefulness, and evidence

4.0Good
4.0/ 5

Potentially useful with some tradeoffs

The evidence base is useful, but some claims depend heavily on the formula.

Risk flags are low for most users, though the finished product can still irritate.

Source
synthetic
Evidence
moderate
Irritation
low
Clogging risk
low
How reviews are scored

Quick decision guide

Useful, but context matters

Bis-Stearoxydimethylsilane is generally a lower-concern ingredient when the full formula suits your skin.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Bis-Stearoxydimethylsilane.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

A synthetic silicone polymer modified with stearic acid chains, giving it both emollient and film-forming properties.

How it works

It spreads evenly over the skin or hair, creating a thin, flexible film that locks in moisture and provides a smooth, velvety feel. It also helps other ingredients spread more uniformly.

Pros

Silky, non-greasy feel

Leaves skin feeling smooth and velvety without a heavy or oily residue, making it ideal for daytime moisturizers and primers.

Low irritation risk

Rated as very low on the irritation scale, so it's generally well-tolerated even by sensitive skin types.

Cons and cautions

Synthetic origin

As a lab-made silicone, it may not align with natural or minimalist skincare preferences.

Potential buildup on hair

In hair products, frequent use can lead to silicone buildup, which may require clarifying shampoos to remove.

Best for

  • People with normal to dry skin looking for a smooth finish
  • Those who prefer lightweight, non-greasy moisturizers

Use caution if

  • Individuals who strictly avoid silicones in their routine

Usage tips

Apply products containing this ingredient to slightly damp skin for better spreadability.
If using in hair care, alternate with silicone-free products to prevent buildup.

Safety summary

Bis-Stearoxydimethylsilane is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic rating, making it suitable for most skin types. No significant safety concerns have been raised by regulatory bodies.

Research notes

While not extensively studied in isolation, silicones in this class have a long history of safe use in cosmetics. Their film-forming and emollient properties are well-documented in formulation science.

Common label clues

Typical concentration
0.5% to 5%
Regulatory status
Approved for use in cosmetics globally, including by the U.S. FDA and EU CosIng database, with no known restrictions at typical use levels.
Common uses
Moisturizers, Sunscreens, Makeup primers, Hair conditioners, Lip products
Environmental note
Silicones like this one are not biodegradable, but they are not known to accumulate in living organisms. Some manufacturers are exploring more eco-friendly alternatives.

Good to know

  • This ingredient is often used in combination with other silicones to fine-tune product texture.
  • It is considered safe by major cosmetic safety panels.

Common questions

What is Bis-Stearoxydimethylsilane in beauty products?

Bis-Stearoxydimethylsilane is a type of silicone that spreads easily on the skin and forms a light, breathable film. It helps products feel silky and smooth, reduces tackiness, and can improve the texture of creams and lotions. Because it's non-greasy and low-risk for irritation, it's commonly used in moisturizers, sunscreens, and makeup primers.

What does Bis-Stearoxydimethylsilane do in a beauty product?

It spreads evenly over the skin or hair, creating a thin, flexible film that locks in moisture and provides a smooth, velvety feel. It also helps other ingredients spread more uniformly.

Is Bis-Stearoxydimethylsilane safe for most people?

Bis-Stearoxydimethylsilane is considered safe for use in cosmetics at typical concentrations. It has a low irritation and comedogenic rating, making it suitable for most skin types. No significant safety concerns have been raised by regulatory bodies.

Who should be careful with Bis-Stearoxydimethylsilane?

Individuals who strictly avoid silicones in their routine

Research sources

CosIng - European CommissionOpenPersonal Care Council - Silicones SafetyOpenPubMed - Silicones in DermatologyOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.