There is nothing quite like finally getting comfortable in bed, only to wake up an hour later feeling far too warm.

For some people, sleeping hot is an occasional nuisance. For others, it is a nightly battle of throwing the duvet off, turning the pillow over and searching for the elusive cool side of the bed.

Cooling mattresses are designed to make that experience more comfortable — but not all cooling mattresses work in the same way.

Some rely on gel or temperature-focused materials. Others use pocket springs to encourage airflow. Some combine several different technologies into a hybrid construction.

So rather than simply asking whether a mattress is “cooling”, it is worth asking a better question: where does the heat actually go?

What actually makes a mattress cool?

Your mattress sits directly underneath you for hours at a time, so its construction naturally affects how warm the sleeping surface feels.

Foam, springs, covers, fillings and even the space underneath the mattress can all play a part.

A mattress may feel cooler because it allows air to move through its internal structure. It may use a breathable cover. It may contain a cooling comfort material designed to manage heat at the surface. Or it may combine several of these features.

This is why two mattresses can both be marketed as “cooling” while feeling quite different to sleep on.

Why pocket springs can help hot sleepers

One of the simplest ways to think about pocket springs is to picture the space between the springs.

Unlike a solid block of foam, a pocket sprung core contains individual springs arranged throughout the mattress. That more open internal structure can allow air to circulate through the mattress.

This does not automatically make every pocket sprung mattress cool. The comfort layers above the springs still matter. A thick or dense foam layer can change the overall feel compared with a more open construction.

But if you are naturally a warm sleeper, a pocket sprung mattress is certainly worth considering — particularly when paired with breathable fillings or cooling comfort materials.

Memory foam vs hybrid for hot sleepers

This is where the choice becomes more interesting.

Traditional memory foam has a close, enveloping feel. It moulds around the body and can create a comfortable sense of cushioning, but that close contact can also make some sleepers feel warmer.

That does not mean you need to rule out memory foam completely. Modern mattresses can combine memory foam with cooling materials, breathable covers, ventilation features or spring systems underneath.

Hybrids take this idea further. By combining foam or gel comfort layers with pocket springs, they can offer the cushioning feel of foam while retaining a more open spring-based core.

For a hot sleeper who likes the comfort of foam but doesn't want an entirely foam mattress, a hybrid can be a particularly appealing compromise.

Is gel really cooler?

Gel is probably the first thing most people think about when they hear the words “cooling mattress”.

But gel should not be treated as a magic ingredient.

Gel can be incorporated into foam or comfort layers to help manage heat, but the overall sleeping experience still depends on the rest of the mattress.

The cover, foam construction, spring system, mattress depth and surrounding sleep environment all contribute.

A mattress with a cooling gel layer and an open spring core is a very different proposition from an all-foam mattress with a relatively thin gel-infused surface.

So when comparing cooling mattresses, look at the whole construction, rather than stopping at the word “gel”.

Why breathability matters

Heat isn't the only thing that can make a bed feel uncomfortable. Moisture matters too.

If you perspire during the night, a breathable sleeping surface can help the bed feel fresher rather than warm and clammy.

Look for mattresses with breathable covers, vented borders, spring systems and materials chosen to encourage airflow.

It is also worth remembering that your mattress is only one part of the sleep environment. Duvets, sheets, mattress protectors, bedroom temperature and even the bed base can influence how warm you feel.

Who should avoid certain mattress constructions?

If you are a particularly warm sleeper, an all-foam mattress with a very close, enveloping feel may not be your first choice.

This isn't because memory foam is inherently hot. Modern foam mattresses vary enormously, and some use cooling materials or more breathable structures.

It is simply that a dense, deep foam construction can feel warmer to some people because your body is surrounded by more material.

Likewise, if you dislike the feeling of sinking into a mattress, a heavily contouring foam model may not be the best match even if it has cooling technology.

Hot sleepers who prefer a more responsive surface may find a pocket sprung or hybrid mattress more comfortable.

A few cooling mattresses worth considering

Rather than simply choosing the mattress with the longest list of cooling features, here are three different approaches from the current Mattress365 range.

Your mattress isn't the whole story

Even the most thoughtfully designed cooling mattress can struggle if the rest of your bed is trapping heat.

Your duvet, sheets, mattress protector and bed base all sit around the mattress and can affect airflow and moisture management.

A suitable bed base can allow air to circulate beneath the mattress, while a breathable protector and lighter bedding can help prevent your sleep environment from becoming unnecessarily warm.

Our Cooling Mattress Buying Guide also explores cooling materials, covers, toppers and protectors.

What about cooling covers?

The cover is the first material your body comes into contact with, so it can have more influence on the initial sensation than you might expect.

Cooling fabrics can be designed to feel fresh against the skin, while breathable materials can help manage moisture and airflow at the surface.

Some mattresses also use temperature-focused fabrics or materials designed to create a cooler surface sensation.

But the cover is only one layer. A genuinely comfortable cooling mattress needs the construction beneath it to make sense too.

Are cooling mattresses good for everyone?

If you naturally sleep warm, a cooling mattress can be a worthwhile consideration. But you don't necessarily need one simply because a mattress has cooling technology.

If you are someone who regularly feels cold in bed, for example, a heavily cooling-focused mattress may not be your priority.

Likewise, if you love the deep, enveloping feel of traditional memory foam, choosing a mattress purely because it has a highly ventilated spring system may leave you disappointed with the feel.

Comfort still comes first. Cooling technology should complement the way you like to sleep rather than dictate it.

What should hot sleepers actually look for?

If you tend to wake up warm, start by looking beyond the marketing language.

Look for:

• A pocket sprung or hybrid core that allows more airflow.
• Breathable covers and materials.
• Cooling or temperature-focused comfort layers.
• Vented borders or air vents where appropriate.
• A comfort level that suits your normal sleeping position.
• A mattress construction that doesn't feel excessively enclosed if you dislike a warm, enveloping sensation.

Most importantly, look at how those features work together.

The coolest mattress is the one that works with you

There is no single material that guarantees a cool night's sleep.

Gel can help manage heat. Springs can create airflow. Breathable covers can make the surface feel fresher. Hybrid construction can bring several of those characteristics together.

But your own comfort matters just as much. The firmness you prefer, the way you sleep and how much you like to sink into your mattress can all influence which cooling construction feels right.

For many hot sleepers, a hybrid or pocket sprung mattress with breathable materials is an appealing place to start. For others, a cooling memory foam construction may offer the combination of comfort and temperature management they are looking for.

The important thing is to look beyond the word “cooling” and understand what is actually happening inside the mattress.