Coolflex Kids Hybrid Mattress review: a breathable, budget-friendly mattress perfect for wriggly sleepers

Price on writing: From £129 | Buy now from MattressNextDay

Related: Find out how the Coolflex compares with other tried-and-tested options in our guide to the best mattresses for kids

Overall verdict

As a mum of three, I appreciate that I might be throwing caution to the wind and tempting every fate out there by making the following statement, but here it is anyway: since using the Coolflex mattress, my son has not had a single bad night’s sleep. True, at seven, he’s a good sleeper anyway and has been since toddlerhood, but he’s also a sweaty, restless sleeper, so I’ve been pleasantly surprised to find that the Coolflex Kids Hybrid Mattress has proven more than a match for him, even during the hottest UK summers on record.

True, we’ve only had it for six weeks so far, but I can’t really fault much about this mattress. The hybrid design combines foam which moulds to the body with supportive pocket springs. It’s nice and firm which gives ideal support for a growing child, but it’s not so firm as to be uncomfortable. And starting from just £129, it’s excellent value for money - I can absolutely see us using it for years to come.

How I tested the Coolflex Kids Hybrid Mattress

I tested the Coolflex Kids Hybrid Mattress for just over six weeks as my seven-year-old son's main mattress. He used it on a bunk bed (lower bunk), replacing a very old mattress we’d had for several years. During testing, I took note of how easy it was to get upstairs and unpack, whether it needed time to expand or air, how it fitted his bed and sheets, and how comfortable and supportive it felt for nightly use. As the testing time frame coincided with the hottest UK summer on record, I also took note of how well the mattress kept my son cool or as cool as it was possible to get in a 30 degree bedroom overnight.

How did the Coolflex Kids Hybrid Mattress arrive?

The mattress arrived vacuum-packed and rolled up in a surprisingly small box. I was able to carry it upstairs and unroll it without needing help. Once the vacuum was broken and the mattress was unrolled, it started to expand straight away.

We left it to fully expand over the course of a day and my son began sleeping on it that night. It was extremely easy to place on my son’s lower bunk in his bunk bed and very simple to dress with the usual single-sized mattress protector and bedsheets we’ve always used.

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Did it have an initial odour?

There was a faint smell when I first unpacked it, but it cleared within a few hours and had gone by bedtime.

How easy was it to install?

We placed the mattress on the bed once we had unrolled and unpacked it, and let it finish expanding there. It was easy for two of us to lift it onto the lower bunk, I think it also would have been fine for me to lift it on myself. I would recommend two adults to lift it onto a top bunk or a high sleeper bed, however. The 16cm depth worked well with the layout of the bed and the anti-slip base meant that it fitted snugly in the frame straight away.

Does it fit standard bedsheets easily?

Yes, all standard single-sized bedsheets have fitted without any slippage or issue.

How easy is it to keep clean?

We haven't had to clean the mattress yet, but the care instructions advise regular vacuuming and spot cleaning any stains. Unlike the cot mattresses we've had in the past, it didn't come with a removable cover, so it's definitely a good idea to use a mattress protector.

How firm is the Coolflex Kids Hybrid Mattress?

The firmness is medium-firm, which is ideal for support and alignment when it comes to growing children. My son has certainly had no complaints when sleeping on the mattress. Like many a seven-year-old, he doesn't tend to spend much any time staying still and, judging from the positions I find him in during the night and in the morning, this isn't isolated to his waking time, so it’s great to know that the mattress is providing him with the supportive base he needs no matter what improbable position he ends up in.

How comfortable is it?

My son has never had any trouble getting to sleep on the mattress, and after lying on it myself, I can confirm it's very comfortable. The foam layer means it moulds to your body while the springs give you deeper support. It feels nice and even and there’s no creaky noises or strange dips.

How well does my son sleep on it?

My son has slept really well on this mattress since day one. He settles well, hasn’t woken up at night once since using it (touch wood) and thanks to its breathability, he has seemed less sweaty than he did on his old mattress, even on warm nights. I’ve had to drag him out of bed for school some mornings, which is always a sign of a comfy mattress I think!

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How breathable is it?

The knitted cover gives the mattress a good degree of breathability. While it’s obviously not a magic cure for the 30C+ degree temperatures our bedrooms reached during the heatwave, I did find that my son was able to sleep on it comfortably enough even on the warmest nights (with the use of a fan) and I didn’t get the same ‘It’s too hot to sleep!’ complaints I got from his sisters. He didn’t seem to sweat quite so much with it either, which is reassuring.

What are the stand-out features of the Coolflex Kids Hybrid Mattress?

I would say the features which have mattered the most during our testing timeframe are the mattress’ breathability and its comfort. My son’s sleep environment has been put to the test by the heat over the last few months and it’s been reassuring to know his mattress is more than capable of rising to the challenge. Plus, as a wriggly sleeper, it’s great to have a mattress which adapts with the sleeper and provides a comfortable surface wherever they find themselves.

What is the longevity like - can you see it lasting?

It’s hard to judge longevity as we’ve only been using the mattress for six weeks so far, but there’s nothing in our experience with it thus far to suggest that it won’t last for many years to come. There’s a five year guarantee as well, which is reassuring.

Is it reversible?

No. The Coolflex Kids Hybrid Mattress is single-sided, so it does not need to be flipped. The brand recommends rotating it head to toe regularly to help keep it supportive.

Do you think it represents good value for money?

I think, at £129, it represents excellent value for money. It does everything you’d want a mattress for a growing child to do and I can see it being used for many years to come. 

About the author

Jenny Wonnacott has been working as a Content Editor for Mumsnet since 2022 and, as part of the core baby and child editorial team, has been responsible for the bedtime category of articles, buyers' guides and review content for most of this time. She has extensive experience of researching, testing and reviewing a wide range of baby and toddler sleep items from travel cots to swaddles, baby monitors to toddler beds.

A mum of three, Jenny has done her fair share of late-night Googling in search of the best baby sleep aids - and now puts that experience to good use by ensuring Mumsnet’s reviews and buyers' guides are practical, trustworthy and based on genuine insight. She works closely with medical and industry experts and Mumsnet’s community of parent testers to make sure every product recommendation truly lives up to Mumsnet's goal of making parents’ lives easier.

About Mumsnet Reviews

All Mumsnet Baby & Child product reviews are written by real parents after weeks of research and testing – this includes recommendations from the Mumsnet Talk boards. We work hard to provide honest and independent advice you can trust. Sometimes, we earn revenue through affiliate (click-to-buy) links in our articles. However, we never allow this to influence our coverage.

All prices correct at time of publication