I've tested four different Emma mattresses in the past few years – after sleeping on it for a month, the new Hybrid ThermoSync is my favourite yet

This Emma Hybrid ThermoSync Mattress review puts the hybrid mattress-in-a-box under the spotlight to see how it fares under Ideal Home test conditions for the best mattresses.

Initially, I tested this mattress for a month whilst I helped my parents move house. Then my mum, who has recently undergone a knee replacement, tested it after her operation. Here's what we thought.

In a nutshell

I've tested several Emma mattresses before. In fact, I swapped out my older Emma Luxe Cooling Mattress to try out the Emma Hybrid ThermoSync Mattress for this review.

The ThermoSync is a medium-firm hybrid mattress, and I found it to be slightly softer than the Luxe Cooling, which I appreciated as I found side sleeping much more comfortable on the ThermoSync. I also found it offered improved temperature regulation compared to the Luxe Cooling which meant no overheating at night. By the end of my testing period, I would choose the ThermoSync as my favourite of all the Emma mattresses I've reviewed.

I also appreciated the ThermoSync's mattress-in-a-box delivery, which is great for those with awkward access, and the 200-night sleep trial that allows you to test out the mattress for yourself in your own home before committing.

However, as with all Emma mattresses, it was only delivered to my doorstep rather than my room of choice, and there's no white glove delivery option to choose from (where the mattress is unboxed and installed onto your bedframe for you).

Beyond that, the only area this mattress performed a little less well is its edge support. It dipped considerably when I sat on its edge, although, as of writing, I didn't find this affected my sleep as I could still sleep close to the edge without sinking. Whether this would be the case if I was heavier, I'm not sure.

This mattress isn't cheap, but I did find it improved my sleep quality compared to the more affordable Emma mattresses I've tried. All in all, it's definitely my top recommendation from the brand's range.

Specifications

• Type: Hybrid
• Construction materials: Memory foam, Thermosync foam, Elastic Airgocell foam, HRX foam, pocket springs
• Sizes: UK single, UK small double, UK double, UK king, UK super king, EU Single, EU Double, EU Queen
• Tension: Medium
• Height: 27cm
• Side handles: Yes
• Flip or rotate: Rotate
• Manufacturer sleep trial: 200 nights

1. Comfort

For me, the medium-firm Emma ThermoSync is a Goldilocks level of comfort when I compare it to the firmer Emma Premium and Emma Luxe Cooling mattresses I've previously tested. It reminds me of the Emma Original mattress in terms of its comfort, and I found it to be a mattress I could acclimatise to immediately.

This makes sense considering that the ThermoSync and Original have almost identical firmness levels. According to Emma, 'on a scale from 1 (firm) to 10 (soft) the Emma Hybrid Thermosync is a 7.5 (medium)', while Emma states the Original is a 7 on the scale.

Ordinarily, I like to sleep on my side and when I tried the firmer Premium, I experienced a kind of dull pain in my hips and back after a time, which is why I switched back to a medium-firm mattress.

So, as a side and back sleeper, the ThermoSync was noticeably comfier from the offset. It doesn't overly dip down when I nestle onto it, and it holds up across my shoulders and hips when I'm on my side.

As I mentioned above, though I was the one to initially test out this mattress for several weeks, my mum has gone on to inherit it, with a different set of comfort needs. After undergoing a knee replacement, she found it difficult to sleep easily, but did note that shifting to this mattress was a huge help when she was out of hospital.

If you're spending this much on a mattress, you'll obviously want it to be comfier than a hospital bed, but the real defining difference was that this mattress made it easy to get back to sleep even when she was restless. It has a very cushioning feel too, which proved immensely helpful for resting her healing leg.

My mum sleeps on her back and is also prone to back pain, so her comfort levels are harder to meet than mine. She immediately found this mattress to be noticeably more comfortable than her old mattress and hasn't had an occurrence of back pain since using it. Perhaps no surprise, as a medium-firm mattress is usually recommended by experts as the best mattress for back pain.

2. Motion isolation

According to Emma, this mattress should 'absorb any motion on the mattress ensuring uninterrupted sleep' and therefore provide tip-top motion isolation. This was something I put to the test when I slept with my mum in this bed whilst I helped her move house.

As I've noted, she is a fairly restless sleeper so there is a high risk of being woken by her during the night. Compared to the old mattress we were sleeping on in our house before we moved, the motion isolation here was worlds apart.

Though she often tosses and turns, I was able to stay in a deeper sleep without being interrupted by a fidgety co-sleeper.

3. Responsiveness

The make-up of this mattress includes a layer of foam underneath its temperature regulating foam that's designed to 'enhance airflow and cradle all the achy bits, like a full body hug'.

As well as making the mattress comfortable, I think that this increased air flow does help to make the feel of the surface more responsive. When you press down it, it immediately springs into action. Or when you shift around on it, it's not as if you've fallen into a soft trench you can't wriggle out of. That makes sleeping soundly even if you're prone to moving about much easier.

With her recent surgery, my mum often needed to change sleeping positions whilst being mindful of her knee and found it similarly responsive.

4. Temperature regulation

During my previous testing of the Premium and Original Emma mattresses, my biggest complaint was poor temperature regulation and poor breathability.

I'm usually a cold sleeper, but when I previously tested the (now discontinued) Emma Premium mattress, I regularly woke up due to overheating and my partner (a hot sleeper) was beside himself after a few nights of broken and sweaty sleep.

The ThermoSync mattress aims to address this with specialist 'ThermoSync foam' which is 'infused with graphite particles' to absorb the excess heat created by your body when you sleep. So I had high hopes that my previous gripe had been solved.

So far, I can't complain of any heat-related issues when sleeping on the ThermoSync, even within my mum's small bungalow which can get very warm, very quickly. I certainly haven't experienced the middle-of-the-night heat surge that I had with the Premium.

Unlike me, my mum is a hot sleeper, and she doesn't have any heat-related complaints either, so she can attest to this tech working for warmer sleepers too.

5. Edge support

Good edge support has been an important factor for me when sharing a bed with my mum so that we have our own sleeping sections without feeling like we're going to roll off the edge. It's also been a factor because of my mum's bad knee, meaning she needs an even surface she can get up from when she's feeling less mobile.

Emma says the ThermoSync is engineered with an 'additional foam edge support for more stability', and although I haven't felt like I'm too close to the edge at any point when sleeping, I was surprised when I sat on the edge of the mattress as to how much I felt it dipped.

Repeatedly, when I tested the edge support by perching on the sides, I felt like I was dipping far more than I'd like to, and my mum also noticed the edge support was lacking when she was putting on her socks and shoes, which is a process that takes her a bit of time.

If you also have similar mobility issues, the Sealy Newton Posturepedic Mattress is the mattress with the best edge support, gaining the seal of approval from our reviewer who struggles with lower back pain.

All in all, I would say the edge support is where this mattress is slightly let down. Although it didn't affect my sleep during testing, it may be more of an issue if I were heavier, and it's a factor I'll be keeping an eye on to see if the edges do dip more over time.

6. Sleep trial

If you're on the fence about which mattress to choose and can't get to a showroom to test a mattress in-store, Emma offers a decent length sleep trial of 200 nights on all its mattresses.

Seeing as I've tested mattresses that I initially found comfortable, but then struggled with over time (I'm thinking of those nights spent overheating on the Emma Premium) knowing that I could send the ThermoSync back, even after initially thinking it was a good fit, gives me peace of mind.

The brand itself says that it can take up to six weeks for your body to fully adjust to a new mattress, a fact I can attest to first-hand. So it's definitely worth opting for a mattress with a sleep trial in my opinion.

7. Ease of care

I've always been a bit unsure on when I'm meant to be flipping or rotating my mattress, so I reached out to Emma via the customer chat function to ask them how to care for my new mattress.

The customer service representative told me that it's a good idea to rotate the mattress, advising me to do so every 3-6 months to 'increase the mattress's durability' and 'help the foam inside to be distributed evenly, ensuring that no dips develop'.

As I write this, it means it's time for me to rotate the mattress to avoid any dips. This is easily done thanks to the large fabric handles on the side of the mattress, which are a necessary addition to a mattress with this much weight when it is out of the box.

8. Delivery

The ease of Emma's mattress-in-a-box delivery is a huge plus point for me. This mattress was delivered to coincide with moving into a new house, but, as always, there were moving delays, meaning that the mattress had to sit in its box for a while before it could be unfurled.

Keeping it neatly packaged up was so much easier than if it was a flat delivery. And its compact box is also a bonus for anyone with awkward delivery access to negotiate.

That said, I inquired as to how long I could keep the mattress within the confines of its box and Emma recommended no longer than four weeks. If you're moving house, that's a great window of time to allow you to get yourself sorted and still know you have somewhere to sleep if you need to at the end of the day.

The delivery of the mattress was seamless, with the courier calling me when they were within an hour of arrival. However, as with all Emma mattresses, delivery is to the doorstep only. There's no option of delivery to your room of choice, or 'white glove delivery' where the mattress is unboxed and installed onto your bedframe for you.

If this is a deciding factor in your mattress purchase, you might want to consider a Simba, Brook + Wilde, or Bensons for Beds option instead where these services come as standard or as added extras.

Luckily, I had help on hand to do the heavy lifting, and I found removing the mattress from its packaging fairly straightforward.

You place the curled-up mattress onto the bed and then remove the outer packaging and wait for the inflation to take place. This can create a bit of a plastic-y smell, so I always make sure to open the windows a little beforehand, but in the case of this mattress, I didn't notice any particular odour.

I find it's best to unbox this mattress in the morning to give it a good amount of time to inflate. When I returned six hours later, the mattress looked ready to go.

9. Third-party reviews

Emma is a well-known mattress brand, almost synonymous with the mattress-in-a-box product. Despite how popular the brand is, the TrustPilot score for the brand is a little concerning at 2.8 stars out of 5 from 49,991 reviews at the time of writing.

Reading through the reviews, lots of the 1-star ratings relate to the sleep trial or product guarantee and voice frustration at not being able to exchange or receive a refund for a product that didn't meet expectations. Others take issue with how the product arrives post-delivery or with the lack of availability to engage with customer service assistants.

I can't say that I've experienced any of these issues with the brand personally, and have always found myself connected via live chat to an agent on the website within minutes when I have a query or problem, but it's a factor worth being aware of.

10. Value for money

As of writing, a ThermoSync mattress costs £819 for a double and £918 for the king-size I tested. However, Emma often offers discounts that can see the price slashed, so it's worth holding out for a sale period when you shop.

That said, this mattress still costs considerably more than the brand's most affordable mattress, the all-foam Emma Original mattress, which I've also tested. I found both mattresses similar in comfort, with the biggest difference being that the ThermoSync slept far cooler and didn't cause me to overheat at night. If you're a heavier-weight person, the ThermoSync's pocket-spring layer will likely also offer better support. If neither overheating or support are factors for you, the best value is with the Emma Original mattress.

Price-wise, this mattress also sits bang in the middle of the most popular mattresses of its competitor, Simba. The Simba Hybrid Original mattress costs £799 for a double, and the Simba Hybrid Pro mattress costs £1149.

Thanks to its more extensive delivery and customer care options, its greater commitment to sustainable manufacturing, and Simba's higher Trustpilot rating, we still think Simba's are some of the best mattresses you can buy at this price point. But I've been really impressed by the Emma Hybrid ThermoSync mattress, so if you find it on sale when you come to shop, it's a great mattress to test out at home and see if it nails your sleep requirements as it has mine (and my Mum's).

How I tested

Molly Cleary

I'm Molly, Ideal Home's Kitchen Appliances Editor and I get to put all kinds of kitchen essentials to the test for my day job, which is a lot of fun. As a reviewer by occupation, I put those skills to the test when trying out this Emma Hybrid ThermoSync mattress, after trying three other mattresses from the brand in the past.

My sleep stats:

Sleep position: back or side

Tension preference: medium-firm

Sleep problems: occasional overheating and hip pain

Height & weight: 5"7 and 11 stones

For this review, I put the Emma Hybrid ThermoSync mattress through Ideal Home's mattress testing process, evaluating how comfortable this mattress was, judging whether it had an impact on temperature regulation and looking at motion isolation and responsiveness. I also judged how easy it was to receive, unbox and move this mattress.

As part of the review, I also looked into customer service from Emma and used the brand's outreach functions myself, as well as researched third-party reviews on sites like Trustpilot.