What Is a Serum, and Do You Actually Need One?
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Short answer: A face serum is a lightweight, concentrated product applied after cleansing and before moisturiser, built around one or two ingredients for a specific goal, such as brighter-looking skin, a more even-looking tone or extra hydration. You do not strictly need one. A serum is how you add a goal to the basics of cleanser, moisturiser and sunscreen.
| Question | Answer |
|---|---|
| What it is | A thin, concentrated leave-on product with a focused job |
| Where it goes | After cleansing, before moisturiser and sunscreen |
| How many you need | None is fine; one or two is plenty |
| Does it replace moisturiser | Usually not |
| How soon you see a difference | From the same day to twelve weeks, depending on the ingredient |
What does a face serum actually do?
It delivers a higher share of one or two chosen ingredients than a moisturiser can carry, in a texture thin enough to layer.
A moisturiser has to do several jobs at once: soften the surface, slow water loss and feel pleasant on the skin. That takes oils, butters and emulsifiers, which leave limited room for anything else. A serum drops most of that so it can focus. It is usually water- or gel-based, sinks in quickly and leaves space for the moisturiser and sunscreen that go on top.
That focus is the whole point. A good serum is built around a clear goal, and its ingredient list should make that goal obvious within the first few lines.
Is a serum the same as a moisturiser?
No. A serum supplies targeted ingredients; a moisturiser seals the routine and keeps water in.
Many serums hydrate, because hyaluronic acid, glycerin and sodium PCA appear in many of them. Hydrating means attracting water. A moisturiser also reduces how fast that water escapes, which is why nearly every serum's directions end with "follow with your moisturiser". Skipping that step is a common reason a hydrating serum seems to stop working after a few hours, especially in heated rooms.
| Product | Texture | Main job | Where it sits |
|---|---|---|---|
| Serum | Thin liquid, gel or light emulsion | Deliver one focused goal | After cleansing |
| Moisturiser | Cream or lotion | Soften and slow water loss | After serum |
| Face oil | Oil | Soften; add a final comforting layer | Last before sunscreen, or mixed into cream |
| Sunscreen | Cream, fluid or gel | Daily UV protection | Always the final morning step |
Do you actually need a serum?
Not to have a complete routine, but it is the most efficient way to work on one specific thing.
A cleanser, a moisturiser and a daily sunscreen cover what skin needs from you. Everything beyond that is optional. If you are happy with how your skin looks and feels, there is no obligation to add anything. If there is one change you would like to see, a serum is usually the best place to put that effort, because it is where a formula can concentrate on a single goal.
Which serum suits which goal?
Choose by the change you want, and expect each ingredient to work on its own timeline.
Our four serums show how differently they can be built:
| Serum | Built around | Goal | When to use | Timeline | Fragrance |
|---|---|---|---|---|---|
| Vitamin C Brightening Serum | 2% natural vitamin C, 1% ferulic acid, 1% sea buckthorn, hyaluronic acid | Brighter-looking, more even complexion | Morning | 4–6 weeks | Contains fragrance |
| Peptide-Powered Anti-Aging Serum | 2% hexapeptide-11, 1% ginkgo biloba extract, hyaluronic acid | Smoother, firmer-looking skin; the look of fine lines | Morning and evening | 8–12 weeks | Contains fragrance |
| Bioactive Prebiotics Jelly Serum | Prebiotics, hyaluronic acid, sodium PCA, glycerin | Lightweight hydration; comfortable-feeling skin | Morning and evening | Immediate | Contains fragrance, alcohol and patchouli oil |
| Exosome & Niacinamide Serum | Apple-derived exosomes, niacinamide, a little lactic acid, hyaluronic acid | More even-looking tone; refined-looking texture | Morning and/or evening | Hydration at once; tone over weeks | Fragrance-free |
Two notes. The jelly serum's fragrance, alcohol and patchouli oil suit many skins, but if yours is easily irritated, patch test it first. And the exosomes in the Exosome & Niacinamide Serum are plant-derived, from apple. The evidence for them in skincare is young, and they have nothing to do with the exosome procedures offered in clinics.
For more depth on two of these, read our guides to when to use vitamin C and what peptides do.
How do you apply a serum?
On clean skin, a few drops or one or two pumps, pressed in before your moisturiser.
- Cleanse and pat dry, leaving skin very slightly damp if the serum is hydrating.
- Use the amount on the label, typically two or three drops or one or two pumps for face and neck.
- Press or gently massage it in, avoiding the eye area unless the product says otherwise.
- Wait until it no longer feels wet, then apply moisturiser.
- In the morning, finish with sunscreen.
If you use two serums, apply the thinner one first. Our layering guide covers the full order.
What a serum won't do
It changes how skin looks and feels; it does not change your skin's structure, and it does not work instantly unless its job is hydration.
- It will not replace sunscreen. None of our serums contains SPF.
- It will not erase lines or spots. Good serums can reduce the look of them over weeks.
- It will not speed up because you use more. Extra product mostly ends up on your pillow.
- It will not fix a reaction or a painful skin problem. Those need a doctor or pharmacist.
Common mistakes
- Stacking four serums at once. Results become impossible to read, and irritation becomes more likely.
- Buying two serums that do the same job. Two hydrating serums is the classic duplicate.
- Skipping moisturiser. Hydration fades faster without something on top.
- Judging too early. Give vitamin C four to six weeks and peptides eight to twelve. Anything promising faster is overselling.
Frequently asked questions
Do I apply serum before or after moisturiser?
Before. Serums are thinner and go on clean skin; the moisturiser goes on top to soften and slow water loss. In the morning, sunscreen is always the last step.
Can I use a serum without a moisturiser?
Some oily skins feel fine with a hydrating serum alone in humid weather. Most people do better with a moisturiser on top, especially in winter or in heated rooms, because a serum alone does little to hold water in.
How many serums should I use?
One is enough for most routines, and two is a sensible maximum. Choose serums that do different jobs, and add the second only after the first has had a few weeks on its own.
Can I use a serum around my eyes?
Only if the label allows it. Our serums are directed at the face and neck, and the Exosome & Niacinamide Serum specifically says to avoid the eye area. For that thinner skin, use a product made for it.
When will I see results from a serum?
Hydration is noticeable the same day. Vitamin C brightening takes four to six weeks of daily use, and peptides need eight to twelve weeks. Keep everything else in your routine unchanged while you wait.
All four serums, with key ingredients and directions, are in our skincare collection.
Last reviewed: October 2026.