When to Apply Vitamin C Serum.

When to Apply Vitamin C Serum

When it comes to brightening up dull, tired looking skin, nothing – and I mean nothing! – is better than vitamin C. Vitamin C is an essential vitamin that offers tons of health benefits when consumed orally, but it also makes for a very powerful skincare ingredient. There are a ton of different ways that vitamin C is incorporated into skincare products.

Generally, my view is that vitamin C serums have the highest concentrations of active vitamin C and allow for better skin penetration (compared to other products with vitamin C like moisturizers or oils). Applying a vitamin C serum at the right time can help the skin to get the most benefits from the product. There’s always been a healthy debate over what time to apply it, but I personally think that morning is best (after all, you want that brightening effect!). Today we are going to talk about it. The benefits of vitamin C, when to apply it, the serums I personally love, and some tips for how to use it in your own skin care routine. I hope it’s helpful!

When to Apply Vitamin C Serum

I think it really helps to understand how vitamin C works to appreciate the product. (It can also help you to choose which products to use and when to apply them!)

What Does Vitamin C Do For Your Skin?

Evens out the skin tone.

This is, in my opinion, the number one reason to use a vitamin C serum. Depending on the strength of the serum, it can fade hyperpigmentation, dark spots and discolorations, etc.

Brightens the skin.

This is another of my favorite vitamin C serum benefits and something I personally really notice, as it’s pretty much instant. Any time my skin is looking dull or tired, I reach for vitamin C. It perks up the skin pretty much instantly!

Boosts collagen production.

This also helps with the skin’s elasticity. And more collagen = plumper skin, meaning that fine lines & wrinkles are less visible.

Reduces the signs of aging.

Vitamin C is an anti aging powerhouse, known for neutralizing free radicals. If you don’t know what free radicals are, here is a quick explainer. Our skin is constantly exposed to stressors like UV radiation and pollution. These stressors trigger the formation of free radicals (also known as reactive oxygen species). These damaging compounds can accumulate on the skin and inhibit the production of key proteins like collagen and elastin. Vitamin C protects the skin from oxidative stress and helps to neutralize these free radicals before they can accumulate. This helps to protect your skin from damage (note: vitamin C is not an alternative to sunscreen!).

It is interesting to note that once vitamin C is absorbed, the protection it offers seemingly lasts for days! Vitamin C helps the body synthesize collagen and increases cell turnover. This is part of why skin looks brighter from vitamin C: dead skin cells are replaced by new ones more quickly.

the Best Time To Apply Vitamin C Serum

I like to apply vitamin C serum in the morning to get those brightening benefits. That is what experts recommend too, but honestly there isn’t really a “wrong” time to apply them. You will want to apply after cleansing and toning the skin, and before moisturizer and sun protection. For me, vitamin C is probably the most important part of my morning routine (aside from SPF, of course). I try to apply it at the same time every day.

Which vitamin C Serum should I use?

I have tried so many – but remember, it’s a huge part of my job to try out new skin care product! The photo above has three of my current favorite vitamin C serums, plus a favorite vitamin C face oil. The most potent vitamin C serums I have tried are Bluemercury’s Vitablast and the Dr. Dennis Gross one. I also really love this one from Paula’s Choice (this is especially amazing for fading dark spots and sun damage – it made a real difference on my chest area). If you have sensitive skin or prefer something fully “clean,” give the Ursa Major or this one from Biossance a try. Keep in mind that this all depends on your skin type, I have dry skin.

Speaking of dry skin (and it is not a serum) but I really love this oil from Biossance. It has a much lower concentration of vitamin C but makes you so glowy. (Oils are the last step, they go over moisturizer!) Lastly (and not an oil, this Biossance moisturizer is very very good!).

When choosing a vitamin C serum, it’s also worth knowing that it pairs very well with vitamin E and ferulic acid. Vitamin C and vitamin E actually stimulate each other’s antioxidant power, and ferulic acid is famously an antioxidant booster that actually doubles C + E’s ability to fight free free radicals! (And that is why Skinceuticals’ C E ferulic is so famous. Writing and researching this post inspired me to order a new bottle as I stopped using it when I ran out of my bottle but I do really love it).

how to apply vitamin c serum

Start with a low dose.

If you have sensitive skin, it might be smart to start with a lower dose. Vitamin C side effects include itching, redness, irritation, and burning. I have personally never experienced any of these symptoms (even with all of the products I test and try!) but if you experience any of these symptoms, stop using the product.

Apply to clean, dry skin.

You are going to want to apply your vitamin C to clean, dry skin right after washing or applying toner. It’s important that your skin not be wet when you apply it. Vitamin C (especially L-ascorbic acid) is very unstable which means it loses potency when exposed to air, light, and water. So any water on your face can actually reduce its efficacy. The more you know, right?

Allow to dry before applying other products.

Again with the stability issues! Adding other products right afterward could potentially deactivate the vitamin C, so you want to make sure you’ve let it fully dry. Just a minute or so should be all it takes! If you are also using a hyaluronic acid, you can pat that on after your vitamin C.

Do not combine with other actives!

I have seen conflicting advice here but personally like to play it safe. You do not want to combine vitamin C with other active ingredients like BHAs, AHAs, retinol, niacinamide, or benzoyl peroxide. Especially if you have sensitive skin!

My rule is always one active per routine (this is another reason to save vitamin C for the morning, if you are using an acid or retinol product at night, you’ll want to wait until morning to use vitamin C). Combining actives can lead to a bad reaction like flaking, irritation, weird bumps, or dryness. Less is more. One active at a time, period. It’s worth noting that hyaluronic acid is fine to combine with vitamin C. Its name is deceptive; it’s a hydrating ingredient, not an exfoliant!

Store it properly!

Ideally, your vitamin C serum will come in an opaque bottle to help with stability. But because light and air can reduce the formula’s stability, you want to keep it in a cool, dark place. Also, this goes for all skincare but especially vitamin C: make sure to close the lid properly!

Disclosure: If you buy something through my links, I may earn an affiliate commission, at no cost to you. I only feature things I truly love here. Thanks for your support.


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  1. Stacey Hoffman:

    Vitamin c serum is always a must for me. I actually really like the super goop one!

    3.21.24 Reply
  2. Heidi:

    Skinceuticals CE Ferulic is my fave! Been using for 2 years & have no intention of switching it up. I stock up when Dermstore does Skinceuticals sales.

    3.22.24 Reply
  3. Theodora:

    The Skinceuticals C E is the only *very* expensive skin product I use, but I think it’s worth every penny!!!!!

    3.22.24 Reply
  4. I’m confused. You say do not use vitamin c with water but you can use hylauronic acid serum. But this serum requires moisture to work. So how do you use both?

    3.23.24 Reply
    • Just let it dry in between steps and you will be fine. Vit C, let it dry. HA, let it dry. Moisturizer to lock it all in.

      3.23.24 Reply