11 Best Vitamin C Serums of 2024, Tested by Experts

These vitamin C serums are a mix of GH Seal holders, top-rated products from trusted brands and favorites from editors and dermatologists. While they weren't all tested in the Lab, GH Beauty Lab scientists have performed many tests on the best anti-aging serums. In these tests, the products are first label-masked to eliminate bias, then distribute them to dozens of consumer testers, who apply the products daily for a set time period between four and 12 weeks. In the Lab, analysts use the Visia Complexion Analyzer device to track changes in skin during the product's use, including hyperpigmentation, lines and wrinkles, and pores.

Testers also share feedback on how their skin looks and feels during and after use and any perceived changes in skin. They comment on many elements of the formulas, including texture, absorption, ease of use and scent. Hundreds of data points are then tallied to find the best vitamin C serums.

In theory, almost everyone can incorporate a vitamin C serum into their skincare routine. However, Dr. Marmur cautions that too much vitamin C can potentially irritate skin. It depends on your skin type, but she personally recommends products that contain between 10 to 15% potency for best results.

Vitamin C is highly effective in its pure form, according to Wnek, but it is a tricky ingredient to formulate with because it is very unstable and can degrade with exposure to oxygen, light, water and high pH. That means that while it is a hero ingredient, its properties are difficult to stabilize — and because of that, some vitamin C serums and other skincare products work better (and for longer) than others.

The powerful ingredient comes in a variety of forms, which "differ primarily in their stability, solubility and ability to penetrate the skin," says Wizemann. "Some types may be better suited for certain skin types or concerns, while others may provide improved stability for products that face exposure to air or light."

If you have dry skin, you might want to look for added moisturizing ingredients like hyaluronic acid; if you have very sensitive skin or rosacea, start slowly and carefully as your skin is already compromised and prone to irritation. Wizemann explains the differences in the most common forms seen in OTC products:

✔️ L-Ascorbic Acid: The most well-studied form of vitamin C used in skincare products, L-ascorbic acid is highly effective at brightening the skin, reducing the appearance of dark spots and hyperpigmentation, and promoting collagen production. However, it can be unstable and prone to oxidation when exposed to air or light.

✔️ Ascorbyl Palmitate: A more stable form of vitamin C, ascorbyl palmitate is often used in formulations where stability is a concern, such as in moisturizers. However, it does not penetrate the skin as effectively as L-ascorbic acid.

✔️ Sodium Ascorbyl Phosphate: More stable than L-ascorbic acid, this type of vitamin C is less irritating and better for those with sensitive skin but less potent than L-ascorbic acid. It also has antioxidant properties, can help brighten the skin and reduce inflammation.

✔️ Magnesium Ascorbyl Phosphate: Another stable form of vitamin C, magnesium ascorbyl phosphate is often used in skincare products targeting acne-prone or sensitive skin. It has anti-inflammatory properties and can help reduce redness and irritation while brightening the complexion.

✔️ Tetrahexyldecyl Ascorbate: This lipid-soluble form of vitamin C is highly stable and penetrates the skin easily. It is often used in anti-aging formulations to promote collagen production, reduce wrinkles and improve skin texture.

Wizemann shares the benefits of this all-star ingredient:

• Fights free radical damage: Vitamin C neutralizes free radicals generated by UV radiation and environmental pollutants which helps prevent oxidative stress and damage to skin cells.
• Increases collagen production: It helps reduce collagen breakdown which keeps skin elastic and youthful-looking and also slows down aging by stabilizing collagen fibers.
• Reduces signs of aging: By promoting collagen production, vitamin C can help reduce the appearance of fine lines and wrinkles, as well as improve overall skin firmness.
• Diminishes dark spots and hyperpigmentation: It inhibits melanin production by interfering with tyrosinase, the enzyme responsible for creating melanin; this can lead to reduced age spots or sunspots.
• Improves dull skin texture and tone: Using vitamin C can help create a more even skin tone due to its ability to reduce tyrosinase activity and discoloration in skin.
• Hydrates: Vitamin C indirectly contributes to skin hydration by promoting collagen synthesis and improving the skin barrier.
• Brightens: By reducing hyperpigmentation and protecting skin from damaging UV rays, vitamin C can have an overall brightening effect.
• Provides anti-inflammatory effects: Vitamin C prevents the release of certain pro-inflammatory chemicals in the body; this also makes it a treatment option for skin conditions like acne and rosacea.
• Helps wounds heal faster: In addition to speeding up healing, it can also prevent dark spots from forming after an injury or acne.

Yes! When used on a daily basis, a vitamin C serum can help brighten dull skin, diminish acne scars, even out skin tone, hydrate skin and protect it from pollution and UV damage. Once you find the most effective vitamin C product for your skin type, simply apply the vitamin C serum to clean, dry skin once or twice a day, and follow with your favorite face moisturizer to seal in the serum and further hydrate skin.

"It is most common to apply vitamin C in the morning, but some dermatologists feel that nightly application is also beneficial if the serum is well tolerated," says Wizemann. She advises to follow the directions on the packaging, as some mention once daily in the morning while others may say "am and pm."

Wizemann adds that vitamin C is safe to use daily for long periods and works synergistically with other anti-aging agents like sunscreens, tretinoin, antioxidants and alpha-hydroxy acids. If it's too strong for your skin, it may cause stinging, redness and dryness, which typically can be managed with a moisturizer. "When applying vitamin C around the eyes, use caution, as it can irritate," she says.

GH Beauty Lab Senior Chemist Danusia Wnek helped select the picks listed above and contributed her knowledge and research of vitamin C and the effects it can have on skin. She has been testing skincare products including eye creams, serums, night creams and neck creams for over seven years at the Good Housekeeping Institute. She has experience in using specialized skin evaluation lab equipment, regularly polls our consumer panel and weighs in on the benefits of skincare ingredients like vitamin C, retinol and niacinamide.

GH Contributing Beauty Editor Dori Price recently updated this article, adding in more details about the product picks and additional info about testing protocols. She has over 15 years of experience researching and writing skincare stories and is an expert in all face and body skincare product categories, from cleansers to toners, serums, moisturizers, sunscreens, exfoliators, masks, professional treatments and more.

Dori consulted GH Beauty Lab Director Sabina Wizemann on her most recent update, with Wizemann contributing information about different forms of vitamin C, how to shop for serums as well as all of the benefits the ingredient offers. Since joining Good Housekeeping, Sabina has touched, researched, tested and evaluated thousands of products for almost a decade. She carried out various studies from sunscreens (including formulas for sensitive and oily skin and mineral types), night creams, eye creams, makeup cleansers and more.