Is the M&S Comfortably Cool Mattress Topper the best budget topper out there? Our verdict

This cooling mattress topper is plush. It's comfy, it's crafted from 100% cotton, it's vegan-friendly, and naturally moisture wicking. This isn't just a mattress topper, this is the M&S Comfortably Cool Mattress Topper.

It's well-established that M&S makes products that are a cut above the rest. Whilst they might be your go-to for fancy biscuits and a nice bottle of elderflower cordial, they might not be the people who you think of as the experts for cooling sleep. I'm here to tell you that they should be.

I've been sleeping on the M&S Comfortably Cool mattress topper for over a week now. It's designed with a cotton cover that naturally wicks moisture from your body. Of all the models we've tested, this might just be one of the best cooling mattress toppers on the market.

Specifications

Unboxing the M&S Cooling Mattress Topper

Mattress toppers come in all shapes, sizes, and packages. M&S kept it smart and simple, with their carry bag. You can loop your hand through the handle in the shop, or when you're carting this upstairs, and it's easy to swing onto the bed. It's not heavy or a lot to handle. It's simple.

The zip around the bag covers two sides, so it's easy to slip your topper out and onto the bed. I was instantly strucka by how plush it felt. In fact, I think if I was blindfolded, I would have thought this was a summer duvet. It's comfortable and protective, without being too stuffy. 

If you look into the details of the M&S Comfortably Cool Mattress Topper, you'll see that it has all been made in the UK, in an eco-factory. This means that it has lower carbon emissions than one that has been carted around the continent before it landed at your door. 

It's fitted with an elastic skirt, the outside is pure cotton, and the filling is polyester. Whilst cotton is brilliant for naturally cooling your skin, I always bristle at the idea of polyester being included in any product that claims to be 'luxurious' like this. Whilst this does the job of cooling your skin, plenty of experts will tell you that polyester actually traps heat and it's not that breathable either - a surprising option for a cooling topper.

Who would the M&S Cooling Mattress Topper suit?

If you like the idea of luxurious products and quality that you can trust in, the M&S Comfortably Cool Mattress Topper is perfect for you. The brand has made use of cotton's naturally cooling properties, smothering your mattress in plush, thick cotton.

There are plenty of different fillings that you can opt for when choosing a topper and this is one of the thinnest. If you already have a mattress that offers the support you need, the M&S Comfortably Cool Mattress Topper is an ideal option. It feels like lying a thin duvet over the top of your mattress. It doesn't interfere too much in your sleep set-up, but it adds a little comfort and some cooling sleep aids. However, if you're looking for some joint relief or extra support, you might need materials that are a little more robust than the fine, polyester fill of the M&S Comfortably Cool Mattress Topper.

Price wise, this is surprisingly reasonable. The topper is true to size, so if you have a UK double, this'll be just £79. Dunelm's cooling topper is £64, so only marginally cheaper, and this feels like it'll last a lot longer.

How does the M&S Cooling Mattress Topper fit on the bed?

I tested this on a Kingsize bed and was pleased to find that this is perfectly true to size. The elastic bands over the corners of the topper slipped neatly around all the sides of my bed. I didn't have any overhang, just as this didn't come up short on any corners. It was perfect.

My mattress measures 23cm depth. With the topper sitting naturally, I would say that my mattress measured 31cm. As soon as I lay on top of it, a lot of the air that added height got pushed out, which is a relief, as I'm not sure my mattress protector would be able to stretch over another 8cm of bed.

What does the M&S Cooling Mattress Topper feel like to sleep on?

Given that this is called the Comfortably Cool Mattress topper, I was looking at two key areas: is it comfortable? and is it cool?

First, let's talk about comfort levels. As I've mentioned, the fill and structure of the topper makes this airy, so when you lie down, you get that 'it's been a long day and I've just flopped onto the duvet' feeling'. It nice, light, and the cotton feels cool to touch. The air does gradually seep out of it, so the M&S Comfortably Cool Mattress Topper won't be able to revive an old and tired mattress, but it will be able to enhance the plushness of your mattress.

The other factor I mentioned was, is this cool? As a hot sleeper, I would say that this has some subtle, but useful cooling features. Cotton is naturally cooling and moisture-wicking, so that does a gentle job of helping you to stay cool in comparison to a polyester sheet, for example. However, much of this cooling is pretty passive and, once your hot, sweaty, and sticky, this is pretty passive. You'll need to get the fan and ice out to feel proper relief. 

That's not a downfall of the M&S Comfortable Cool Mattress Topper - although I'm not sure how helpful the polyester fill is. This doesn't claim to actively cool you. It does its best with the materials that it has, but it's not going to work miracles. 

You may have also wondered what the glass of water is doing on the topper. It's our test for motion transfer. If you share the bed, you'll know that it's easy to disturb your sleeping partner if you rustle around a lot, especially if you're hot. We sit a glass of water on the bed and watch how stable it is as we move around on the surface. 

A lot of the motion transfer is determined by the mattress, something mine is really good at limiting, but the M&S Comfortably Cool Mattress Topper did a great job of enhancing this. The water didn't slosh or slop around, no matter how much I moved.

How do you clean the M&S Cooling Mattress Topper?

Experts generally recommend washing your mattress topper every three months. You actually shouldn't so it too often, because this will reduce the lifespan of it, but, if three months is up, or it's looking a little worse for wear, you'll need to give it a clean.

Not every topper is suitable for the washing machine, but this is fine to bung in on a 40°C cycle. I'd recommend using a gentle detergent, such as Ecover, but all the guidance M&S gives is not to bleach. Once it's been through the wash, I let mine air dry. However, M&S says you could actually tumble dry this on a low temperature, which is unusual for toppers (and useful if your home has high humidity.

The two things you categorically cannot do to the M&S Comfortably Cool Mattress Topper are ironing it and dry cleaning it. 

How does it compare to other cooling toppers?

I've been testing and researching the best cooling toppers for months, so I've slept on my fair share of options. If you loved the idea of a cooling mattress topper and found yourself a little disappointed at M&S's natural approach, there's an option that'll light up your eyes. The Eight Sleep Pod 3 will pump cold water underneath you as you sleep, actively cooling you down. It's a lot more expensive than the M&S Comfortably Cool Topper (it's nearly £3,000), but it comes with lots of smart sleep tech that just about justifies the price tag.

If you want to keep to a budget and you're wondering what else is out there, the xxx is a team favourite. Like the M&S Comfortably Cool Topper, this uses the natural properties of its materials to transfer heat and moisture away from your body. What's great about the Panda Bamboo is that it's also hypoallergenic, anti-microbial, and it's great for pressure relief. Whilst all of the materials are 100% natural, this feels like memory foam, which is a lot more supportive and cushioning, ideal for side sleepers.

Should you buy the M&S Cooling Mattress Topper?

If you love your mattress but want a thin, extra layer to add some plushness and a little cooling technology, the M&S Comfortably Cool Mattress Topper is a good investment. It feels wonderful to touch and nice to lie on, but it isn't going to revolutionize your bedding. It's a nice flourish to a bed set up and certainly a luxury for hot sleepers. I like it as a little extra, but don't rely on it to keep you cool if you seriously suffer from night sweats.