Guide
How to Use Vitamin C Serum
By the BestCSerum editorial team · Updated 2 October 2026 · How we write and check content
Step by step
1. Cleanse and pat skin dry. 2. Apply a few drops or one pump of serum to the face and neck. 3. Wait about a minute for it to absorb. 4. Apply moisturiser. 5. In the morning, finish with a broad-spectrum sunscreen.
The general rule is thinnest to thickest: serums go before moisturiser, and sunscreen goes last in the morning.
Morning or night?
Morning is the usual recommendation because vitamin C's antioxidant activity complements sunscreen during the day. Night use also works if a serum feels heavy under makeup. Our full explainer on vitamin C morning or night compares both.
Combining with other actives
Vitamin C can be used with hyaluronic acid, vitamin E and ferulic acid without issue. For niacinamide, see vitamin C and niacinamide. With retinoids and exfoliating acids, most people do better using them at different times of day; see vitamin C and retinol.
Storage
Close the cap tightly and keep the bottle away from heat and sunlight. A serum that has turned dark orange or brown has oxidised; see why vitamin C serum changes colour.
Frequently asked questions
+Does vitamin C go before or after moisturiser?
Before. Apply the serum to clean skin, let it absorb, then moisturise.
+Should I apply vitamin C before sunscreen?
Yes. Vitamin C goes under sunscreen. Sunscreen is always the last skincare step in the morning.
+How long does vitamin C take to work?
Brightening and evening of tone usually take several weeks of consistent use. Studies of topical vitamin C typically run for a few months.
Related guides
- Vitamin C Serum with SunscreenWhy vitamin C and sunscreen work well together, which goes first, how long to wait, and why vitamin C never replaces sun protection.
- Vitamin C and Niacinamide Together?Whether vitamin C and niacinamide can be used together, where the old warning came from, and practical ways to layer or alternate them.
- Vitamin C Serums for BeginnersA first vitamin C serum, explained: which forms and strengths suit beginners, how to start without irritation, and serums compared by price and ratings.
- Why Vitamin C Serum Turns Yellow or Brown (Oxidation)Why vitamin C serum changes colour, when an oxidised serum should be thrown away, and how to store vitamin C so it stays effective for longer.
Vitamin C forms mentioned on this page
Sources
General information only, not medical advice. This page has not been reviewed by a dermatologist. If you have a skin condition, are pregnant, or react to a product, speak to a qualified doctor. Product data is checked against named sources; see our methodology.