Moisturiser is one of the most familiar steps in a skincare routine, but what does moisturiser actually do?
At its simplest, a facial moisturiser helps maintain hydration, reduce moisture loss and leave the skin feeling softer and smoother. Different moisturisers achieve this through combinations of ingredients that attract and retain water, soften the skin's surface and form a layer that helps limit water loss.
These ingredients are commonly grouped into three categories: humectants, emollients and occlusives. Understanding how they work can make moisturiser labels much easier to interpret — and help explain why different moisturisers can feel and perform differently.
In this guide, we'll look at what moisturiser is, how it works, its main cosmetic benefits and some of the ingredients commonly used in modern moisturising formulas.
What Is Moisturiser?
A moisturiser is a topical skincare product formulated to help maintain the water content and condition of the outermost layer of the skin.
Although we often talk about “adding moisture”, moisturisers can work in several complementary ways.
Depending on their formulation, they may contain ingredients that:
- attract and retain water
- reduce water loss from the skin's surface
- soften and smooth the way skin feels
- improve the feel of rough or dry skin
- help maintain the skin barrier
Most modern moisturisers combine several of these functions rather than relying on one type of ingredient alone.
Research into moisturiser technology similarly describes humectancy, emolliency and occlusion as central approaches used in moisturising formulations.
What Does Moisturiser Do?
The primary cosmetic role of a moisturiser is to help keep skin hydrated, soft, smooth and comfortable.
Skin naturally contains water, but water can continually move through the outermost layers of the skin and evaporate into the surrounding environment.
A well-formulated moisturiser can help maintain skin hydration by combining ingredients with different functions.
For example:
Humectants → help attract and retain water
Emollients → help soften and smooth the skin
Occlusives → help reduce water loss from the skin's surface
These categories can overlap, and individual ingredients may contribute more than one function within a finished formulation.
The formulation as a whole matters more than simply identifying one “hero” ingredient.
How Does Moisturiser Work?
To understand how moisturiser works, it helps to look briefly at the outermost layer of the skin: the stratum corneum.
The stratum corneum consists of flattened skin cells surrounded by an organised lipid matrix. Maintaining an appropriate amount of water within this outer layer contributes to its flexibility, appearance and comfortable feel.
Moisturisers can support this through different formulation strategies.
Rather than going deeply into skin-barrier biology here, we have a separate guide explaining What Is the Skin Barrier? and how it relates to hydration.
For moisturisers specifically, the three ingredient categories worth understanding are humectants, emollients and occlusives.
Humectants, Emollients and Occlusives: What's the Difference?
These terms appear frequently in skincare discussions, but they describe different functions.
1. Humectants
Humectants are ingredients that help attract and retain water within the outer layers of the skin.
Common humectants used in skincare include:
- glycerin
- hyaluronic acid
- panthenol
- urea
- certain sugars and glycols
Hyaluronic acid is particularly well known for its water-binding properties and is frequently incorporated into hydrating skincare formulations.
Humectants can be found in both serums and moisturisers, which is one reason a hydrating serum and moisturiser can have complementary roles within a routine.
2. Emollients
Emollients help soften and smooth the skin's surface.
They can improve the feel of skin by filling spaces around surface skin cells and creating a smoother, more flexible-feeling surface.
Examples of ingredients that may provide emollient properties include:
- squalane
- shea butter
- certain plant oils
- fatty acids
- some skin-identical lipids
Emollients are particularly important to the sensory experience of a moisturiser — how soft, smooth and comfortable the skin feels after application.
3. Occlusives
Occlusive ingredients help form a layer over the skin that limits water evaporation from its surface.
Examples can include:
- petrolatum
- mineral oil
- dimethicone
- waxes
- certain oils and butters
Different occlusive ingredients provide different textures and degrees of occlusivity.
A moisturiser does not necessarily need to feel extremely heavy to help reduce moisture loss. Modern formulations can combine humectant, emollient and occlusive properties in many different textures.
Research supports the complementary use of these mechanisms: humectants promote water retention within the stratum corneum, while occlusive components can help minimise water loss to the environment.
What Are the Benefits of Moisturiser?
The exact benefits depend on the formulation, but a facial moisturiser may help:
Maintain skin hydration
Moisturisers can combine water-binding ingredients with ingredients that help reduce water loss, supporting hydration in the skin's outer layers.
Leave skin feeling softer and smoother
Emollient ingredients can improve the feel of rough or dry skin and create a smoother-feeling surface.
Help reduce moisture loss
Occlusive components can form a layer over the skin that helps limit evaporation of water from the surface.
Support the skin barrier
The outer layer of the skin relies on an organised combination of skin cells and lipids. Moisturisers containing suitable lipids and moisturising ingredients can help support the condition of this outer layer.
Improve skin comfort
Maintaining hydration and softness can help skin feel more comfortable, particularly when it tends to feel dry or tight.
These are cosmetic skincare benefits. A moisturiser should not automatically be assumed to treat an underlying skin condition.
This distinction is particularly important in Australia: the TGA specifically gives claims such as helping to hydrate and moisturise skin as examples of cosmetic positioning, while claims involving treating or repairing conditions such as psoriasis can move into therapeutic territory.
Does Moisturiser Hydrate the Skin?
Yes — but “hydration” and “moisturising” involve more than simply putting water onto the skin.
A moisturiser may contain a water phase, humectants that help retain water and emollient or occlusive components that help reduce moisture loss and improve skin feel.
This is why a moisturiser often contains several ingredient types working together.
It also explains why hydrating serums and moisturisers aren't necessarily interchangeable.
A lightweight serum may focus primarily on humectant ingredients, while a moisturiser can provide additional emollient and moisture-retaining components.
Moisturiser vs Hydrating Serum: What's the Difference?
A hydrating serum and moisturiser can serve complementary purposes.
A hydrating serum is typically a lightweight formulation that may contain humectants such as hyaluronic acid or panthenol.
A moisturiser generally has a cream, lotion or gel-cream base and may combine humectants with emollient and occlusive components.
In a simple routine, the usual order is:
Serum → Moisturiser
This allows the lighter product to be applied first, followed by the moisturiser.
For a detailed explanation of application order, see our guide to How to Layer Skincare: The Correct Skincare Routine Order.
Key Moisturiser Ingredients to Know
There is no single ingredient that every good moisturiser must contain.
Instead, consider how different ingredients contribute to the finished formula.
Hyaluronic Acid
Hyaluronic acid is a humectant widely used in skincare formulations for its water-binding properties.
Within a moisturiser, it can contribute to maintaining hydration in the outer layers of the skin.
Ceramides
Ceramides are lipids naturally present in the outermost layers of the skin.
Alongside cholesterol and fatty acids, they form part of the skin's lipid structure.
Ceramide-containing skincare products are one formulation approach used to support the skin barrier.
We cover ceramides in greater detail in our separate Ceramides vs Hyaluronic Acid guide rather than repeating that discussion here.
Squalane
Squalane is commonly used as an emollient in skincare.
It can contribute to a moisturiser's smooth texture and help leave the skin feeling soft and conditioned.
Shea Butter
Shea butter provides emollient properties and can contribute richness to cream formulations.
It is often incorporated into moisturisers designed to provide a more nourishing skin feel.
Ectoin
Ectoin is used in cosmetic skincare formulations as a skin-conditioning ingredient.
Rather than evaluating ectoin in isolation, it is more useful to consider how it functions alongside the other ingredients within the complete moisturiser formula.
When Should You Apply Moisturiser?
Moisturiser is generally applied after lighter skincare products such as serums.
A simple morning routine may look like:
Cleanse → Serum → Moisturiser → Sunscreen
A simple evening routine may look like:
Cleanse → Serum → Moisturiser
In the morning, sunscreen should be applied according to its label directions.
There is no need to turn moisturiser application into a complicated routine. Consistency and choosing products that suit your preferences are often more useful than adding unnecessary steps.
Should You Apply Moisturiser to Damp Skin?
Applying moisturiser while the skin still has some surface moisture can be a practical way to incorporate it into a routine, particularly after cleansing.
However, there is no need for the skin to be visibly wet.
The more important point is to apply the product evenly and follow the directions supplied with your moisturiser.
If you are layering it over a serum, allow the serum to settle comfortably before applying the next product.
Do You Need Moisturiser If You Have Oily Skin?
Oily skin and skin hydration are not the same thing.
Sebum refers to oil produced by the skin, while hydration relates to water content.
This means someone with oily-feeling skin may still choose to use a moisturiser.
The texture may simply differ. Some people prefer lighter lotions or gel-creams, while others prefer richer creams.
Rather than assuming that one texture suits everyone, consider how the finished formula feels on your skin and how comfortably it fits into your routine.
For more detail on recognising different skin characteristics, see How to Know Your Skin Type: Dry, Oily, Combination & Sensitive.
How Do You Choose a Moisturiser?
Choosing a moisturiser can depend on:
- your skin's current needs
- preferred texture
- other products in your routine
- whether you prefer fragrance-free skincare
- the overall ingredient formulation
- how the product feels during regular use
A lightweight moisturiser may suit someone who prefers a less rich finish, while a creamier formula may appeal to someone seeking a more emollient feel.
Rather than choosing a moisturiser based only on a single highlighted ingredient, look at the complete formulation.
For readers specifically looking for more detailed guidance around ceramide moisturisers and sensitive-feeling skin, see our separate Ceramide Moisturiser for Sensitive Skin Australia guide.
That keeps the two search intents separate.
Do You Need Both a Serum and Moisturiser?
Not everyone needs the same number of skincare steps.
However, a serum and moisturiser can have complementary functions.
For example, a hydrating serum may provide a lightweight layer containing humectants, while a moisturiser may combine hydration-focused ingredients with emollients and other ingredients that help maintain moisture.
If using both, a simple order is:
Serum first → Moisturiser second
You don't need to add multiple serums simply because they exist. A straightforward routine can be easier to use consistently.
Where REVEA CALM Barrier Support Cream Fits In
REVEA CALM Barrier Support Cream is a fragrance-free facial moisturiser developed as part of the CALM two-step skincare system.
Its formulation combines:
Ceramides NP, AP and EOP + Cholesterol + Phytosphingosine
Multi-Weight Hyaluronic Acid
Ectoin
Squalane
Shea Butter
The formula is designed to help maintain hydration, support the skin barrier and leave skin feeling soft, smooth and comfortable.
For those using the complete CALM routine:
Step 1 — CALM Barrier Support Serum
A lightweight hydrating serum with Multi-Weight Hyaluronic Acid and Panthenol (Pro-Vitamin B5).
Step 2 — CALM Barrier Support Cream
A ceramide moisturiser formulated to follow the serum and help maintain skin moisture.
In the morning, follow with sunscreen according to the sunscreen's directions.
CALM Serum → CALM Cream → Sunscreen
This section is intentionally brief. Readers looking for the complete formulation breakdown can visit REVEA CALM Barrier Support Cream: Ingredients & Benefits.
Frequently Asked Questions
What does moisturiser do to your skin?
A moisturiser helps maintain hydration, reduce moisture loss and leave the skin feeling softer, smoother and more comfortable. Different formulations achieve this using combinations of humectants, emollients and occlusive ingredients.
How does moisturiser work?
Moisturisers generally work through several complementary mechanisms. Humectants help attract and retain water, emollients help soften and smooth the skin, and occlusive ingredients help reduce water loss from the skin's surface.
What are the three main types of moisturising ingredients?
The three commonly discussed categories are humectants, emollients and occlusives. Many moisturisers combine ingredients from more than one category.
What is the difference between moisturiser and serum?
Serums are generally lighter formulations designed to deliver selected skincare ingredients, while moisturisers typically provide a combination of hydration, emollience and moisture-retaining properties. They can be used together.
Should serum or moisturiser go first?
Generally, serum is applied first and moisturiser follows. For a more detailed routine-order explanation, see our How to Layer Skincare guide.
When should I apply moisturiser?
Moisturiser is commonly applied after cleansing and any lighter serums. During a morning routine, sunscreen generally follows moisturiser and should be used according to its label directions.
Can oily skin use moisturiser?
Yes. Skin oil and skin hydration are different characteristics. People with oily-feeling skin may prefer a lighter moisturiser texture.
What ingredients should I look for in a moisturiser?
There isn't one ingredient list that suits everyone. Humectants such as hyaluronic acid, emollients such as squalane and shea butter, and ingredients such as ceramides may all contribute different properties to a moisturising formulation.
The Takeaway
So, what does moisturiser do?
A moisturiser helps maintain the condition of the skin's outer layers by combining ingredients that can support hydration, soften and smooth the skin and help reduce moisture loss.
The three concepts worth remembering are:
Humectants → attract and retain water
Emollients → soften and smooth
Occlusives → help limit water loss
A good moisturiser does not need an unnecessarily long list of headline ingredients. What matters is how the complete formulation works together and how comfortably it fits into your skincare routine.
For REVEA, that philosophy is reflected in a simple approach: hydrate first with CALM Serum, then follow with CALM Barrier Support Cream to help maintain hydration and support the skin barrier.
Written by REVEA Editorial Team
Updated: 15 September 2026
References & Further Reading
- Rawlings AV, Canestrari DA, Dobkowski B. Moisturizer technology versus clinical performance. Dermatologic Therapy. 2004;17(Suppl 1):49–56. doi:10.1111/j.1396-0296.2004.04s1006.x.
- Lodén M. Role of topical emollients and moisturizers in the treatment of dry skin barrier disorders. American Journal of Clinical Dermatology. 2003;4(11):771–788. doi:10.2165/00128071-200304110-00005.
- Purnamawati S, Indrastuti N, Danarti R, Saefudin T. The role of moisturizers in addressing various kinds of dermatitis: a review. Clinical Medicine & Research. 2017;15(3–4):75–87.
- Lipozencić J, Pastar Z, Marinović-Kulisić S. Moisturizers. Acta Dermatovenerologica Croatica. 2006;14(2):104–108.
- Therapeutic Goods Administration. Determining if your product is a cosmetic or therapeutic good. Australian Government Department of Health, Disability and Ageing.
