The best niacinamide serum for you is one at a strength your skin tolerates, usually 5 to 10% to start, in a texture that suits your skin type. Niacinamide is for a dull-looking tone, visible pores and shine; vitamin C for a brighter-looking tone; retinol, used in the evening and introduced slowly, for fine lines and uneven texture. For the look of dark marks after pimples, niacinamide, tranexamic acid or azelaic acid plus daily SPF is a sensible start. Begin with one active, not three.
Niacinamide, vitamin C or retinol: which one do you need?
| Active | Choose it for | When to use it | Good to know |
|---|---|---|---|
| Niacinamide (vitamin B3) | A dull-looking or uneven tone, visible pores, shine | Morning, evening or both | Sold from about 5% to 20%; start lower if your skin is reactive |
| Vitamin C (ascorbic acid or a derivative) | Dull-looking skin, a brighter-looking tone | Morning or evening; in the morning, follow with SPF | Close the cap well and keep it away from heat and sun |
| Retinol (a form of vitamin A) | Fine lines, rough or uneven texture, the look of pores | Evenings only, a few times a week at first | Daily SPF; ask a doctor first if you are pregnant or breastfeeding |
| Tranexamic acid (TXA) and arbutin | The look of dark spots and uneven tone | Morning or evening | Often combined with niacinamide in one serum |
| Azelaic acid | Marks after blemishes, skin prone to breakouts and redness | Start once or twice a week | Pair with SPF on days you use it in the morning |
A few label notes help. Korean niacinamide formulas often add centella, panthenol or hyaluronic acid. Vitamin C appears either as pure ascorbic acid or as a derivative such as 3-O-ethyl ascorbic acid or ascorbyl glucoside; derivatives are generally more stable in the bottle, and both vitamin C serums in this guide use one. Retinol is the active most likely to leave skin dry or tingling at first, so use it in the evening, start slowly and wear sunscreen by day.
How strong should a niacinamide serum be?
Korean niacinamide products run from around 5%, common in creams and toner pads, to 10% and 20% in concentrated serums. Higher is not automatically better: Isntree tells you to use its 20% serum sparingly and adds several forms of hyaluronic acid to soften the dry feel that high-dose niacinamide can leave.
- New to actives or reactive skin: start with 5 to 10%, once a day.
- Used niacinamide before without trouble: try 10% morning and evening if your skin stays comfortable.
- Want a more concentrated step: move to 20% only if 10% suits you, and use just a few drops.
- Any strength: stop if stinging, redness or flaking does not settle.
Which serum should I pick for my skin?
Not sure of your skin type? Our skin quiz can help. Examples in Keauty's Korean serum collection and related collections include:
Oily skin and visible pores
Jumiso Niacinamide 10% Serum 40ml pairs 10% niacinamide with tranexamic acid and succinic acid in a fast-absorbing, non-sticky texture. Jumiso aims it at excess sebum and the look of pores and says it is free of fragrance and artificial colouring. If you already use niacinamide, Isntree Hyper Niacinamide 20 Serum 20ml is a concentrated 20% serum with arbutin, zinc PCA and several forms of hyaluronic acid. Use 2 to 3 drops and wear sunscreen the next day, as the brand advises.
Dull-looking skin and uneven tone
Innisfree Vitamin C Green Tea Enzyme Brightening Serum 30ml combines a vitamin C derivative (3-O-ethyl ascorbic acid, 20,000 ppm) with a Jeju green tea enzyme, aimed at skin tone and texture. Use it at the essence step and massage it in from the centre of the face outwards. For more choice, browse our brightening skincare.
Sensitive skin that wants niacinamide and vitamin C
Mary&May Rice niacin 10% Triple Vitamin Serum 80ml pairs 10% niacinamide with 10,000 ppm of a vitamin C derivative, plus vitamin E, glutathione and 30,000 ppm panthenol. Mary&May describes it as tested on sensitive skin, and its ingredient list includes no fragrance. Patch test first, as with any new active.
The look of dark spots and marks after blemishes
Medicube TXA Niacinamide Serum 30ml combines 5% tranexamic acid, 10% niacinamide and 2% arbutin for the look of dark spots and uneven tone. Medicube calls it low-irritation and fragrance-free, but its ingredient list includes rose flower oil, so patch test first if your skin is reactive. Anua Azelaic Hyaluron Soothing Serum 30ml has 10% azelaic acid with three types of hyaluronic acid and is made for skin prone to breakouts and redness. Anua suggests starting once or twice a week, building up slowly, and pairing it with SPF 30 or higher when you use it by day. More options are in our dark spot collection.
Your first retinol
Innisfree Retinol Cica Repair Ampoule 50ml wraps retinol in a liposome with centella and ceramide, and the formula also contains niacinamide. Innisfree describes it as mild, but start slowly anyway: one or two pumps in the evening, a few times a week. The brand asks you to wear sunscreen while using it.
Dr.Ceuracle PDRN & Retinol Shot Ampoule 30ml pairs salmon PDRN with retinol coated onto fine marine sponge spicules in a cushiony cream texture, for skin that is starting to lose firmness and smoothness. Dr.Ceuracle suggests starting in the evening with a small amount on a limited area, pressing it in rather than rubbing, and wearing sunscreen every day. Find more in our Korean ampoules collection.
How do you fade the look of dark marks after pimples?
First check what kind of mark you have. A flat pink, red, purple, brown or black area left after a blemish can be a colour change in the skin rather than a scar. The American Academy of Dermatology (AAD) explains that a true acne scar changes texture: it is raised or indented. A dark spot serum cannot fill an indented scar or flatten a raised one.
For flat marks, keep the routine simple:
- Keep new breakouts in check with a routine for blemish-prone skin.
- Do not pick or squeeze. Squeezing and scratching can prolong healing and make marks or scars more likely.
- Moisturise if your routine leaves skin feeling dry.
- Protect outdoors with a broad-spectrum SPF 30 or higher, and avoid tanning.
- Add one mark-focused active, such as niacinamide, tranexamic acid or azelaic acid, and give it several weeks.
The AAD names azelaic acid as one option for the dark spots that can remain after acne clears. Harsh scrubs, repeated peels and stacked acids can create new irritation rather than faster results. See a dermatologist for deep or painful breakouts, raised or indented scars, or marks that keep coming back. For a new spot in the meantime, see our guide to pimple patches and spot products.
How do you brighten dull-looking skin?
"Dull" describes how skin looks, not why. Dryness, a rough surface, irritation and recent sun can look similar, so start with a calm baseline before adding a glow product.
- Cleanse with lukewarm water and a mild cleanser, without scrubbing.
- Moisturise if your skin feels dry or tight.
- Protect exposed skin with sunscreen, used as its label directs.
- Add one brightening active, such as the vitamin C or niacinamide serums above, and keep the rest of the routine the same for a few weeks.
The AAD advises against scrubbing, because friction can irritate skin, and supports moisturiser for dryness and regular sun protection. Do not start a new acid, scrub, retinol and mask at once: more exfoliation is not automatically more radiance. Burning, marked redness, swelling or flaking that does not settle is a reason to stop and go back to a simple routine.
In a Nordic winter, dull-looking skin can simply be dry skin. Cold air outdoors and heated air indoors both leave skin feeling tight, so try a richer moisturiser over your serum before a stronger active.
Can you use niacinamide, vitamin C and retinol together?
Yes, with some planning. Some formulas already combine niacinamide with a vitamin C derivative, such as the Mary&May serum above, and the Innisfree retinol ampoule contains niacinamide. Vitamin C and retinol need more care: Mary&May's own three-serum set puts brightening in the morning and retinol at night, and Innisfree warns that sensitive skin may react when its retinol is combined with vitamin C or peeling products. If you are unsure, use them on different evenings.
A simple way to fit all three in:
- Morning: cleanser, toner, vitamin C or niacinamide serum, moisturiser, sunscreen.
- Evening: cleanser, toner, retinol on retinol nights or niacinamide on the others, then moisturiser.
- First weeks of retinol: two or three evenings a week, with no acids or scrubs on those nights.
For more pairs to space out, read which skincare ingredients not to mix. If retinol leaves your skin dry, our guide to retinol and the sandwich method shows how to layer it with moisturiser.
Do you need sunscreen with vitamin C and retinol in the Nordics?
Yes. Both retinol products above ask for daily sunscreen, and Isntree asks for it the day after its 20% niacinamide serum. Apply it as the last morning step, over your serum.
From late autumn to late winter the Nordic sun sits low and UV is usually low, which can make it a gentler time to start retinol. Retinol users should still follow the brands' advice to wear sunscreen every day, especially on bright days and on snow, which reflects sunlight. From around March or April UV rises quickly, so keep daily SPF 30 or higher until autumn.
FAQ
Is niacinamide good for oily skin?
Yes, it is a common choice. Brands use niacinamide for shine and the look of pores, and Jumiso adds succinic acid to its 10% serum for sebum control. Keep a light moisturiser too, as oily skin can still feel dry.
Should I use vitamin C in the morning or at night?
Either works. If you also use retinol, keep vitamin C for the morning and retinol for the evening, or use them on different evenings if you are unsure. Finish every morning routine with sunscreen.
Can I use retinol when pregnant or breastfeeding?
Ask your doctor first. Dr.Ceuracle says not to use its retinol ampoule during pregnancy or while breastfeeding, and your doctor can tell you which actives suit you during this time.
Can a serum remove acne scars?
No. Raised or indented scars change the texture of the skin, and a serum cannot rebuild or flatten them, so ask a dermatologist about your options. Flat marks are different: with daily SPF and a suitable active, their look can fade over time.
How long should I try a new serum before judging it?
Give one product several weeks of regular use and change only one thing at a time. Patch test first, and stop if irritation does not settle.
Keauty sells some of the products mentioned here.
Sources
- 10 skin care secrets for healthier-looking skin. American Academy of Dermatology.
- Face washing 101. American Academy of Dermatology.
- Your winter skin survival kit. American Academy of Dermatology.
- Dry skin. DermNet New Zealand.
- Acne: Signs and symptoms. American Academy of Dermatology.
- Acne scars: Overview. American Academy of Dermatology.
- Adult acne treatment dermatologists recommend. American Academy of Dermatology.
- Acne: Tips for managing. American Academy of Dermatology.
This is general cosmetic information. Skin differs from person to person, so patch test new products and ask a doctor or pharmacist about any skin condition.
