Serum vs. Moisturizer: When To Use

Ingredients, Skin Care

“Serum and moisturizer are both essential parts of your skincare routine to treat and hydrate skin.” 

  • Shani 

Building a skincare routine from scratch can be hard. There are many different products that each have their own purpose, and it can be difficult and even frustrating to put them all together for success.

Your days of frustration are about to be over, because I am here to help. Together, we’ll de-mysticize skincare and learn how to order serum and moisturizer in your skincare routine.

What Is Serum?

Serums are typically light liquids that are water or oil-based and come in a dropper bottle. However, serums can also come in lotion and gel forms as well, depending on their purpose. You’ll find that lotion and gel serums are typically designed for dry skin.

These products are not only trendy, but they are an essential part of many skincare routines. Serums are packed with strong ingredients and are often formulated to reduce and prevent visible signs of aging like fine lines, wrinkles, hyperpigmentation, and blemishes.

What Are the Benefits of Serum?

Serums are so important that I recommend using them twice a day. Each serum is different, but here are some benefits that most serums have in common.

Full of Beneficial Ingredients

Serums are often packed with vitamins and ingredients that gently nourish your skin’s radiance while working to smooth out fine lines. In fact, many serums contain hydrating ingredients to help keep your skin as moisturized as possible.

One of my favorite hydrating serums is my Lactic Acid Serum. This serum contains lactic acid, which gently exfoliates and hydrates at the same time. It can also help calm irritation and leave your skin feeling plump and radiant. 

Concentrated Formulas

While other skincare products can contain these ingredients, serums often offer much more concentrated versions. For instance, you may find slight amounts of vitamin C in a moisturizer or cleanser, but many serums offer up to 20% vitamin C formulas for maximum effect. 

Just because serums are concentrated doesn’t mean that they’re harsh on your skin. Even concentrated formulas like my Retinol Reform are designed to keep your skin hydrated and happy while delivering clinical-strength effects.

Absorbs Into Skin

Serums are designed specifically to absorb into your skin so that they can achieve maximum effects. Because these ingredients absorb deeply into your skin, they continue to work their magic for hours after application.

Many strong serums are best suited for nighttime use for exactly this reason. Serums can work on your skin while you sleep so that you can wake up refreshed and ready to go.

Target Your Unique Skin

Because serums can have many ingredients, it’s easy to customize your serum to your specific skincare needs. If you have blemish-prone or aging skin, you can choose a formula with salicylic acid or retinol to help tame the breakouts.

Meanwhile, you can choose gentle exfoliators like lactic acid and hydrating ingredients like hyaluronic acid if you have dry skin. And if your skin is looking dull, serums containing brighteners like vitamin C are essential.

What Is Moisturizer?

Moisturizers are skincare products designed to keep your skin hydrated and supple, and they come in many forms. These can include:

  • Gels, which are lighter and often use water-based formulas
  • Lotions, which are slightly heavier than gels and are typically water-based 
  • Creams, which are thicker and more oily, which makes them a bit more hydrating
  • Ointments, which have the thickest formulas and are best for dry skin

Not only do they hydrate your skin, but moisturizers also often contain small amounts of other ingredients that infuse your skin with brightness and help it look more radiant.

What Are the Benefits of Moisturizer?

Moisturizer is an important part of every skincare routine, but why? Here are a few reasons why you might want to use moisturizer.

Retains Moisture

Many moisturizers are designed not only to infuse your skin with hydration, but also to help support your skin’s natural moisturization processes. Basically, they help your skin keep itself hydrated.

Hydrating ingredients like hyaluronic acid are especially helpful at helping your skin retain moisture. Hydrated skin results in more glowing, healthy skin.

Supports Skin Elasticity

Properly hydrated skin is much better at bouncing back from stress. Your skin is exposed to stress every day, whether environmental stress like sun damage or physical stress like pulling and stretching.

The right moisturizer can help keep your skin soft and supple so that it can stay younger-looking for longer.

Tailored to Your Skin Type

Moisturizers work best when they’re tailored to your skin type. Oily skin thrives best with a moisturizer that lightly hydrates without causing clogged pores like my Weightless Oil-Free Moisturizer

Meanwhile, dry skin needs something a little more substantial. For dry skin, I recommend iS Clinical’s Reparative Moisture Emulsion

When Should I Use Each?

Both serums and moisturizers are vital to every skincare routine. Even though they can sometimes overlap in purpose, they are both very different, and each deserve their own spot in your skincare routine.

I recommend using serum before moisturizer because it’s easier for serum to absorb into clean and dry skin. This is especially true if you use an exfoliator beforehand. Since serum depends on absorption to do its job, you’ll want to time it for maximum absorption.

This arrangement also helps make sure you get the most out of your serums. Not only does more serum get into your skin, but moisturizers can also seal your serum against the skin to make sure your serum has time to work.

Since serums are so strongly formulated, your skin might take time to adjust to them. During this time, you might experience a little more dryness than you’re used to. 

This is a normal part of beginning serum use, and it’s nothing to worry about, but I recommend choosing a hydrating moisturizer to help your skin transition.

I recommend including serums and moisturizers in your morning and evening skincare routines. Your sensitive facial skin is exposed to many environmental stressors throughout the day, and this is one of the best ways to help keep your skin bouncing back day after day.

Your morning serum should be something hydrating and full of vitamins and antioxidants. Our favorite morning serum ingredient is vitamin C because vitamin C can work with sunscreen to help your skin resist sun damage.

However, your evening serum should be reparative. This serum will do the heavy work while you sleep, so I recommend exfoliating serums that target fine lines and wrinkles. Your moisturizer should stay the same in both routines.

Sum it All Up

While moisturizers and serums can perform similarly, they couldn’t be more different! Serums are often concentrated formulas that are designed to treat specific skincare needs. Meanwhile, moisturizers are formulas that keep your skin hydrated.

Even though they’re different, these two skincare products complement each other perfectly. They’re both powerhouse products, but they work much better together.

Follow my blog for more of my skincare tips, and make sure to browse my selection of hand-picked serums and moisturizers to find something that fits your unique skin.


Skin Serum: What it Can and Can't Do | Harvard Health

How to Pick the Right Moisturizer for Your Skin | American Academy of Dermatology

Do You Really Need a Skin Care Routine? | Northwestern Medicine