What's the difference between C-Tetra and C-Tetra Luxe?

C-Tetra is our original, best-selling vitamin C serum. It's the perfect option for those who are new to vitamin C or those with sensitive skin, who still want visible age-defying results. C-Tetra Luxe is our supercharged vitamin C serum - ideal for those looking for clinical brightening and nourishing power. Both serums are formulated with stabilized tetrahexyldecyl ascorbate.

Can I use C-Tetra alongside retinoids?

Absolutely. In fact we recommend the daily use of these 2 powerful actives as our proven pairing for more youthful-looking skin. Apply vitamin C in the morning and vitamin A at night for proven age-defying results.

Can I use C-Tetra if I'm pregnant or breastfeeding?

As a cosmetics company, we are unable to provide product advice in relation to medical conditions such as pregnancy. We would recommend discussing the ingredients with your physician or obstetrician before use. As general guidance, this product does not contain any ingredients which we would recommend to avoid during pregnancy, unless advised by your physician.

How does the new C-Tetra formula differ from the old one?

The new C-Tetra formula has been optimized to enhance both performance and skin feel, while maintaining the lightweight texture you know and love. We’ve introduced centella asiatica to help support skin comfort, alongside a refined, silkier finish for an improved application experience.

Can I expect different results with the new C-Tetra formula?

You can expect the same visible brightening and antioxidant benefits, now with an enhanced skin experience. The upgraded formula helps to support skin comfort with the addition of centella asiatica, while still delivering fast absorption and a lightweight, radiant finish.

C-Tetra™

7% Stable Vitamin C Serum Full Details

Benefits
Brighten
Even
Glow

Bestseller

C-Tetra™

7% Stable Vitamin C Serum Full Details

Benefits
Brighten
Even
Glow

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Clinically proven to brighten skin and restore visible skin radiance.*

Formulated with 7% tetrahexyldecyl ascorbate, a stabilized, low-irritation form of vitamin C, this lightweight serum targets visibly uneven skin tone and the look of fine lines. Enhanced with soothing centella asiatica to ensure a comfortable application for even the most sensitive skin.

Further fortified with vitamin E, this antioxidant powerhouse also protects the skin against the aging and damaging effects of free radicals for a more youthful and healthy-looking complexion overall. Suitable for those who are new to vitamin C, or those with sensitive skin.

C-Tetra™

KEY BENEFITS

Boost Skin Radiance

89% agree their skin has a visible healthy glow in 7 days^[2]
'
Brighter, More Even Complexion

Proven to visibly brighten the skin tone, for a more even and healthy-looking skin appearance.
Gentle on Skin

Rich in soothing properties, centella asiatica helps to soothe and support all skin types, especially sensitive skins.
Lightweight Nourishment

This jojoba (pronounced 'huh-hoh-ba') seed oil-based formula delivers effective yet non-greasy nourishment for visibly softer and comforted skin.

PROVEN RESULTS

Before After

4 weeks to visibly brighten skin*
4 weeks to visibly improve evenness of skin tone*
1 use for visibly improved skin radiance*
7 days to soothed skin**

*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin. **Proven via independent consumer study conducted over 4 weeks on 60 participants with sensitive skin.

HOW TO USE

If you're new to C-Tetra, we recommend a patch test at least 24 hours before first use. Learn how to patch test here.

Step 1

After cleansing in the morning, massage 4 drops across the face, neck and décolletage.

Step 2

As part of our CSA Philosophy, we recommend using vitamin C plus sunscreen in the morning and vitamin A at night.

Not sure what order to layer your serums? Take our serums layering guide quiz here.

KEY INGREDIENTS

7% Stabilized Vitamin C (tetrahexyldecyl ascorbate)

A low-irritation form of vitamin C that delivers exceptional antioxidant protection against harmful free radical damage while brightening and supporting the skin's natural collagen levels for a visibly even, more youthful-looking complexion.
Vitamin E

A powerful antioxidant, vitamin E works to deeply nourish and soften the complexion.
Centella Asiatica

Rich in soothing properties, centella asiatica helps to soothe and support all skin types, especially sensitive skins. .
Full Ingredients

THE SCIENCE BEHIND THE FORMULA

Ultra-gentle & perfect for visibly radiant skin.

DANIEL ISAACS Chief Product Officer

It is exceptionally difficult to formulate a vitamin C serum that will retain its power over time. That's because vitamin C is notoriously unstable, meaning its effectiveness can be compromised when it comes into contact with light, heat or air. That's why we have chosen to formulate C-Tetra with an extremely stable form of vitamin C (tetrahexyldecyl ascorbate), so you can be sure that your vitamin C is still as potent and effective 6 months after you first opened it.

SUSTAINABILITY CLAIMS

Provenance provides confidence for sustainability claims; helping to prevent ‘green-washing’ and empowering conscious consumers to purchase in line with their values. Provenance ‘Proof Points’ are all third party verified and evidenced through supply chains.

GOOD TO KNOW

NO ARTIFICIAL FRAGRANCE
NO SYNTHETIC COLORS
PARABEN FREE
CERTIFIED BY THE VEGAN SOCIETY

GUIDE TO LAYERING

Not sure where to start? Create your customized skincare routine in 8 clicks.

FAQS

What's the difference between C-Tetra and C-Tetra Luxe?

+
C-Tetra is our original, best-selling vitamin C serum. It's the perfect option for those who are new to vitamin C or those with sensitive skin, who still want visible age-defying results. C-Tetra Luxe is our supercharged vitamin C serum - ideal for those looking for clinical brightening and nourishing power. Both serums are formulated with stabilized tetrahexyldecyl ascorbate.
Can I use C-Tetra alongside retinoids?

+
Absolutely. In fact we recommend the daily use of these 2 powerful actives as our proven pairing for more youthful-looking skin. Apply vitamin C in the morning and vitamin A at night for proven age-defying results.
Can I use C-Tetra if I'm pregnant or breastfeeding?

+
As a cosmetics company, we are unable to provide product advice in relation to medical conditions such as pregnancy. We would recommend discussing the ingredients with your physician or obstetrician before use. As general guidance, this product does not contain any ingredients which we would recommend to avoid during pregnancy, unless advised by your physician.
How does the new C-Tetra formula differ from the old one?

+

The new C-Tetra formula has been optimized to enhance both performance and skin feel, while maintaining the lightweight texture you know and love. We’ve introduced centella asiatica to help support skin comfort, alongside a refined, silkier finish for an improved application experience.
Can I expect different results with the new C-Tetra formula?

+

You can expect the same visible brightening and antioxidant benefits, now with an enhanced skin experience. The upgraded formula helps to support skin comfort with the addition of centella asiatica, while still delivering fast absorption and a lightweight, radiant finish.

C-Tetra™

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C-Tetra™

7% Stable Vitamin C Serum Full Details

C-Tetra™

7% Stable Vitamin C Serum Full Details

KEY BENEFITS

Boost Skin Radiance

Brighter, More Even Complexion

Gentle on Skin

Lightweight Nourishment

PROVEN RESULTS

HOW TO USE

Step 1

Step 2

KEY INGREDIENTS

THE SCIENCE BEHIND THE FORMULA

SUSTAINABILITY CLAIMS

GOOD TO KNOW

GUIDE TO LAYERING

FAQS

What's the difference between C-Tetra and C-Tetra Luxe?

Can I use C-Tetra alongside retinoids?

Can I use C-Tetra if I'm pregnant or breastfeeding?

How does the new C-Tetra formula differ from the old one?

Can I expect different results with the new C-Tetra formula?

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