Sunday Riley CEO Vitamin C Serum: Full Review (And Why You Should Try It)

Last Updated on March 28, 2026 by omgbart

The Sunday Riley CEO vitamin C serum has been in the lineup since 2017. That is a long time in prestige skincare, where products get discontinued, reformulated, or quietly replaced by the next launch. The fact that this one is still here, still reviewed obsessively, and still one of the first things people ask me about when the subject turns to Vitamin C tells you most of what you need to know. This is my original review, updated with everything I know now.

Side note: I live for the Luna Sleeping Night Oil and have had nothing but success with it over the last couple of years. 

What makes the Sunday Riley CEO vitamin C serum different

The formula runs on 15% Tetrahexyldecyl Ascorbate, also written as THD Ascorbate. This is an oil-soluble, highly stable form of Vitamin C. Standard L-Ascorbic Acid, the most common Vitamin C in skincare, is water-soluble and unstable. It oxidises quickly, needs a very low pH to penetrate skin, and tends to sting — especially on freshly shaved skin. THD Ascorbate sidesteps all of that.

Because it is oil-soluble, it moves through the lipid-rich outer layers of skin more readily. It does not require the aggressive pH that makes traditional Vitamin C serums so irritating. At 15%, this is a serious concentration. The same ingredient is used in clinical-grade products sold through dermatologist offices, often at much higher price points.

The supporting cast matters too. Glycolic Acid handles surface-level exfoliation. Saccharide Isomerate Extract reinforces the moisture barrier and reduces the look of pores. A Phytosterols Complex calms redness and sensitivity. The combination does more than brighten.

Texture, scent, and how to use it

The texture is lighter than it looks in the bottle. Milky, almost fluid. It absorbs in seconds. The scent is clean citrus. Nothing synthetic or heavy about it.

I use it in the morning, after cleansing and before SPF. Most Vitamin C formulas sting briefly on post-shave skin. This one does not. That alone kept me coming back.

One pairing note worth knowing: this serum contains Glycolic Acid. Do not layer it with Good Genes on the same application. Both are active exfoliants. Use them on alternate days or morning versus evening rather than stacking them back to back.

It layers well under Luna Sleeping Night Oil, under Tidal, or under any cream moisturiser. It works cleanly beneath SPF, which matters if Vitamin C is part of your morning routine.

Results

Brightness and vibrancy show up within the first few days. The deeper work on sun damage and hyperpigmentation takes four to six weeks of consistent use. That timeline is normal for any Vitamin C formula working at this concentration.

What has changed since 2017

The product now goes by “CEO 15% Vitamin C Brightening Serum” on most retail listings, though the original “Rapid Flash” name still appears on older stock. The formula is the same. Sunday Riley has since expanded the CEO range with an oil, a moisturiser, and an afterglow cream, all designed to layer with this serum. The Sephora exclusivity from launch is gone — it is now at Sephora, Ulta, Space NK, and sundayriley.com directly.

Is it worth $85?

At $85 for 30ml this is not cheap. But THD Ascorbate at 15% is legitimately hard to find at this price point outside of clinical-grade skincare. The no-sting formula and clean layering behaviour make it genuinely usable every day, which is how Vitamin C actually delivers results.

Where to get it

$85 (30ml) at sundayriley.com, dermstore.com (try my code OMGBART for 15-20% discount), sephora.com, ulta.com or libertylondon.com

*press sample

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