Simba Hybrid Ultra mattress review 2024

Is the Simba Hybrid Ultra mattress as luxurious as its promise? We test it to find out…

Simba Hybrid Ultra Mattress review image shows the bed on a podium lit up from below
Editor's Choice
(Image: © Simba Sleep)

Tom's Guide Verdict

The Simba Hybrid Ultra Mattress has 13 sumptuous layers that makes it stand out from your average bed in a box design. It includes Simba’s breathable signature Simbatex open-cell foam and 8,500 springs that create a very relaxing and supportive surface on which to sleep. Having slept on the mattress for over two months, we're very impressed with the excellent pressure relief and comfort it offers. In short, this is a superb mattress for most sleepers. You will, however, pay a premium price for such a luxurious bed. But if you have the budget, buy it – you won't regret it.


  • +

    Well made to a high standard

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    Excellent full body support

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    Great motion isolation

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    Comfortable with a little bounce

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    Strong edge support

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    Breathable sleep surface


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    Very heavy to move around

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    Expensive, even when on sale

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Simba Hybrid Ultra Mattress: Review in brief

When we heard that Simba had launched the Hybrid Ultra that has a whopping 13 layers and is 13 inches / 34cm thick, we were keen to give it a try so we could see if it merits a place in our official guide to the best mattress of the year. We were keen to see how it compares to the popular six-layered Simba Hybrid mattress, which is a slimmer 25cm thick. 

Simba describes this as its ‘dream mattress’ that is a luxurious cocooning fusion’. It has a double layer of Simbatex cooling foam, a ‘thermo-regulating Fusioncool’ layer that includes a blend of kapok, wool and bamboo and up to 8,500 springs carefully positioned throughout the mattress.

Simba Hybrid Ultra specs

Type: Hybrid (spring and foam)
Materials: Foam, natural materials and 8,500 springs.
Firmness: Medium-firm (we rate 6.5-7 out of 10)
Depth: 13 inches / 34 cm
Trial period: 200-night trial
Warranty: 10-year guarantee
RRP: From £2,599 for a single at Simba Sleep

We slept on the Simba Hybrid Ultra Mattress for two months to give it a fair trial and assessed it on design, performance, edge support, motion isolation and whether it kept us at a comfortable temperature throughout the night.

Sleeping on the Simba Hybrid Ultra Mattress has been a pleasure and we didn’t expect to like it as much as we did. It’s a medium firm mattress that was in fact medium firm – not too firm and not too soft like some other ‘medium firm’ mattresses can be. 

After a week of sleeping on the mattress, we could instantly tell how supportive its surface. At this point, we were still keen to know how well the mattress could maintain its edge to edge support over time, however.

The Simba Hybrid Ultra Mattress placed on a bedframe in a stylish industrial bedroom

(Image credit: Simba Sleep)

But after two months, we are pleased to report that the mattress has continued to offer a reassuringly comfortable night’s sleep. There are 8,500 springs inside the mattress and this is something that definitely stands out when comparing this new Simba mattress to even the best hybrid mattresses.

The surface has a wonderful spring and bounce to it that provides excellent pressure relief that makes the body feel supported from head to toe. Motion transfer technology is excellent in this mattress design too - while the springs in the bed do ensure that it gives you a bit of bounce when you move around, we did manage to get into a deep sleep when sleeping alongside our partner.

Neither sides were woken up by the other changing sleeping position or getting in and out of the bed during the night – and vice versa – which is a definite plus here.

Simba Hybrid Ultra Mattress review: Price & trial

  • The Hybrid Ultra is Simba Sleep's most expensive mattress brand’s
  • Save 45% off RRP at time of writing, with a double priced £2,856
  • Comes with a 200-night trial and 10 year guarantee

The Simba Hybrid Ultra Mattress is Simba’s most luxurious offering and it comes with a premium price tag to reflect this. You’ll often find the Simba on sale, however, and at the time of writing it is priced up to 45% off its RRP. 

This comes with ‘free VIP delivery’, whereby the delivery team will remove your old mattress if needed and place your new Ultra Hybrid Mattress on your existing bedframe – and this is something we’re sure you’ll appreciate as this is a heavy mattress. 

When you go to buy you can choose from two cover options. You can buy the mattress with the breathable zip-off cover with or without the ‘Stratos heat control tech’. A free mattress protector also comes included in the price. 

Here are the RRP prices and sale prices for the Simba Hybrid Ultra mattress:

  • Single: £2,599 (normally sells for £1,429.45)
  • Double: £3,799 (normally sells for £2,089.45)
  • King size: £3,799 (normally sells for £2,199.45)
  • Super king size: £4,499 (normally sells for £2,474.45)

These sale prices are reflected across the Simba portfolio and you can currently find all Simba hybrid mattresses on offer. With these price cuts in mind, it’s a good idea to keep an eye on the Tom’s Guide mattress sales round-up when you're ready to buy.

See the Simba Hybrid Ultra: from £1,429.45 at Simba

See the Simba Hybrid Ultra: from £1,429.45 at Simba
For the ultimate in medium firm comfort try the 13 layer, 34cm thick Simba Hybrid Ultra Mattress, which includes a mix of Simbatex foam and 8.400 springs. The Hybrid Ultra mattress is regularly on sale at Simba, with 25% off every size. That reduces the cost of a double to £2,856, plus you'll be eligible for 30% off a premium Simba bedding set.

Simba Hybrid Ultra Mattress review: Design

  • 13 inch/ 34cm thick foam and spring mattress
  • 8,500 springs nestled in 13 layers 
  • Thermo-regulating FusionCool top layer

The Simba Hybrid Ultra Mattress is no ordinary off-the-shelf mattress and each design comes with an impressive 13 layers. To put this into context, Emma’s NextGen Premium Mattress has 6 layers, while the Nectar Premier Hybrid Mattress has 8.

The Simba Hybrid Ultra Mattress is Simba’s most premium design to date and we’ve included it in the Tom’s Guide best hybrid mattress guide as it has many stand out qualities. Within its mattress range, Simba sells five hybrid variations with the 4 layer Simba Hybrid Essential Mattress as its entry level design. For something mid-range you can also consider its best selling 8 layer Simba Hybrid Pro Mattress.

What all the Simba hybrid mattresses have in common is the inclusion of open-cell Simbatex foam, which unlike traditional foam encourages a cooling airflow that helps to keep you at an optimum temperature as you sleep.

Simba Hybrid Ultra Mattress review image shows the different layers inside the mattress

(Image credit: Simba Sleep)

The Simba Hybrid Ultra Mattress has two layers of Simbatex foam, in fact, to help warmth and excess humidity flow away from the body. It also includes a natural cool and dry FusionCool top layer that combines a blend of natural temperature regulating materials such as kapok, wool and bamboo. 

The Simba Hybrid Ultra also stands out for its very impressive number of springs and. Its impressive 8,500 springs have been divided between the layers and carefully positioned for optimum comfort and support. 4,000 titanium alloy Aerocoil micro springs have been placed in the upper layers and are designed to compress individually in response to your body. 

This gives you that nice feeling of pressure relief, while limiting transfer of movement in the mattress so that it doesn’t feel like it’s too bouncy when you move around or that you can feel when your partner is moving on the other side. 3,500 carbon steel Aerocoil micro springs sit further down the mattress to add support. 

These have been designed to gently push fresh air through the mattress as they compress. In the SupportCore base, a further 1,000 pocket barrel springs have been included to optimise the edge-to-edge support. 

Simba Hybrid Ultra Mattress review: Support and comfort

  • A medium-firm mattress that suits most bodies
  • Good edge-to-edge support
  • Supportive top layer with a satisfying bit of 'give'

Good pressure relief for comfort and support is key when choosing the ideal mattress for you and a partner. We slept on the Simba Hybrid Ultra for a couple of months to give it a fair trial and report back our findings. We also used a weight to simulate a body sinking into the mattress and gain further insight into how supportive it is.

We placed an 8kg weight in the middle of the mattress and measured the sinkage at around 1.5", which we think is a fair amount for such a deep and lofty mattress. We think the mattress has a satisfying medium-firm feel that we rate at around 6.5-7 out of 10 in the firmness scale. It has a nice bit of bounce back, while making us feel supported.

Simba Hybrid Ultra sinkage with heaviest weight 8kg

(Image credit: Future)

The sleep surface feels structurally sturdy yet comfortable from edge to edge and the first night we slept on the mattress we felt rested and supported from head to toe. The knitted top layer feels cushioned and smooth to touch that makes the mattress instantly enticing to lay on. 

We didn’t find that the mattress moulded to our body shape like some memory foam mattresses can, but more adapted to our movements from back to side and front. We’ve tried a range of medium firm mattresses that claim to be just that – only to find ourselves suffering from what we call ‘Goldilocks complex’ whereby the mattress is too firm or too soft. But we found the Simba Hybrid Ultra Mattress to be just right – providing a fair bit of cushioning but also keeping our body well raised and supported. 

The mattress also seems to work well for all sleeping positions. Both our back and side sleeper and our front sleeper felt comfortable when moving positions. Our primary tester who is a back and side sleeper noticed how easy it was to change positions too, with the mattress adapting nicely to their hips and spine as they moved. They noted that it’s a very thick and sumptuous mattress and she could really appreciate the sense of luxury when sleeping on the mattress. 

Our front sleeper, who is usually very fussy about what kind of mattress best supports his torso when laying down, noticed how effortless it felt to find a comfortable front sleeping position while sleeping on the Simba Ultra Hybrid Mattress. 

Simba Hybrid Ultra Mattress review: Performance

  • Works well for couples as there’s limited motion transfer
  • Mattress kept us at a comfortable temperature 
  • Deep structure enhances edge support 

We trialled a king size Simba Ultra Mattress over the course of two months to really get a feel for how comfortable and supportive this mattress feels. We tested the mattress in all the major areas of performance including motion isolation, edge support and cooling. 

Motion isolation

Simba Hybrid Ultra mattress review motion isolation test

(Image credit: Future)

For those who share a bed, good motion transfer technology in your mattress is particularly important. With decent motion isolation you’ll be able to move freely on your side of the bed without disturbing your partner and vice versa. 

We tested the motion isolation technology using a 3kg weight and a wine glass. To see whether any movement ripples through the mattress, we dropped the weight 4, 10 and also 25 inches away from the wine glass. We found that at 10 and 25 inches away the wine glass stood tall, but at 4 inches it toppled over. 

In our two-month sleep trial, our testers noted that the bed was a little ‘bouncier’ than other hybrids they had tried – possibly due to the number of springs inside. They noted that when they were awake they did notice when their partner was changing positions on the other side of the bed, but when they were asleep they were impressed with how deep an undisturbed sleep they got. 

Our front sleeping tester also pointed out how little he woke up in the night which was a positive improvement. With the ability to improve sleep in mind, this may be a good option for anyone who is a particularly restless sleeper. 

Score: 4.5 out of 5 

Temperature regulation

Simba Hybrid Ultra mattress review temperature regulation test

(Image credit: Future)

Some cooling mattress materials are better at dispersing heat than others with foam often criticised for trapping the heat. Simba has included materials here that are designed to encourage airflow throughout the mattress and in turn keep the sleeper at the optimum temperature throughout the night. It includes a breathable cover and a natural FusionCool layer that includes a natural blend of thermo-regulating materials such as kapok, wool and bamboo. 

There are two layers of Simbatex inside, which is an open-cell foam that is infused with graphite that is a natural heat conductor that helps excess humidity and warmth flow away from the body.  

We trialled it in the cooler winter months but the room temperature never went below 18°C | 64°F. We topped the mattress with a Simba mattress protector, Simba duvet and Egyptian cotton bedding. Our testers didn’t report being too hot or too cold when sleeping on the Simba Hybrid Ultra Mattress. 

The sheer density of the mattress kept them feeling snug on colder nights without overheating. It would be interesting to see how the mattress fairs on hotter summer nights and we will be updating this feature accordingly with any updates when the weather changes. 

Score: 5 out of 5

Edge support

Simba Hybrid Ultra mattress review 8kg edge test

(Image credit: Future)

Unless you’re under 10 years old, you won’t want to slide out of bed in the morning, which is why good edge support is important when choosing the best mattress. Good support will also prevent premature sagging around the edge of your mattress and give you more space on which to sleep. 

Our testers were impressed at how well this mattress retained its thick and dense structure – particularly when sharing the bed. There are, in fact, 1,000 pocket barrel springs around the perimeter of the mattress that are designed to give good edge-to-edge support. Our testers reported that they were able to sleep right up to the edges of the mattress, without feeling as if were rolling off the sides. They noted that their body weight felt evenly distributed up towards the head and end of the mattress too.  

While they found the sides did squish down a little when sitting around the edge of the mattress and on the corners, they were impressed with how supportive the perimeter of the mattress felt – allowing them to get out of bed slowly and comfortably. 

We used our 8kg weight to test the support on the sides and corners of the mattress. Just like the centre of the mattress, we measured the sinkage at around 1.5inches. This illustrates just how well balanced the mattress filling is and is a good indicator of how much usable sleep surface there is from edge to edge. 

Score: 4.5 out of 5 

Simba Hybrid Ultra Mattress review: Delivery and set up

  • Despatched with Simba’s ‘VIP Delivery’ service
  • We had no issues with off-gassing
  • Arrives fully formed and ready to sleep on

Simba Hybrid Ultra mattress shown on our reviewer's blue fabric bedframe

(Image credit: Future)

When you order the special edition Simba Hybrid Ultra Mattress is comes despatched via Simba’s ‘VIP Delivery service’. This is a free service by a two-person team who will set up the mattress in your home and remove your old mattress and all the packaging it comes too. Once we had placed our order, the courier contacted us to schedule a convenient delivery time – this can take up to five days from the date of ordering. 

On the day of delivery we received a text and phone call to let us know what time to expect the mattress. It arrived fully formed and wrapped in plastic packaging. It is very heavy and was a mission for both of the delivery men to take it up the stairs and position it on the bedframe. The delivery team were swift to remove our old existing mattress, and then take the Simba Hybrid Ultra Mattress upstairs and set it up ready to dress with bedding. 

As the mattress arrives fully formed – as opposed to rolled up and flat packed – there was hardly any off-gassing to contend with, which is that new factory smell you can sometimes get with a new mattress. We left the bed for a few hours just to give it a bit of an airing, but were able to dress it ready for the night without any worry of the odours you can get with off-gassing. 

Score: 5 out of 5

Simba Hybrid Ultra Mattress review: User reviews

  • 129 5-star reviews on brand’s own website 
  • Praise for the comfortable design 
  • Some complaints about it sleeping warm

This mattress is a fairly new edition to the Simba range and was launched in 2023. While there are plenty of reviews on Simba’s longer standing and bestselling Simba Hybrid Pro and the popular Simba Hybrid, the Ultra doesn’t have as many.

You can currently read around 146 reviews of the Simba Hybrid Ultra Mattress with an overall rating of 4.8 stars on Simba’s own website. The reviews we’ve read all seem to be positive, with the consensus that this mattress is a great buy and will provide a very sound snooze. Many of the reviews focus on how comfortable the mattress is with a nice ‘bounce back’ and ‘no rolling off’ the bed.  

If you’re interested to hear what Simba Sleep is like as a company, you can also read brand reviews on the TrustPilot website. You can sift through a staggering 47,168 reviews there, which touch on the company’s customer service, delivery experiences and range of products you can choose from.  

Should you buy the Simba Hybrid Ultra Mattress?

We’ve given the Simba Hybrid Ultra Mattress an overall five-star review as we were so impressed with how supportive and restful its medium-firm design. Having tried the mattress over the course of two months, we feel well equipped to give it a five-star review.

We rated it on performance, design and took into consideration its motion transfer technology, edge support and overall ordering and delivery experience with Simba. Our testers were happy with the quality and comfort of their sleep while snoozing on the Simba Hybrid Ultra Mattress. 

After two months of sleeping on it, they were keen to trade in their previous mattress and permanently upgrade to the Hybrid Ultra, which is testament to how highly they thought of it. 

We think that if you’re someone who likes the feel of a supportive spring mattress but want the luxurious and cosy squish you get from a foam design, this mattress is one to consider. It’s a medium-firm mattress that doesn’t feel too hard like some medium-firm designs can. 

The downside to it, however, is that you will have to pay a premium price tag for it. At the time of writing, a single costs around £1,565.40 on offer with 40% off, which is quite an investment. But if you do decide to spend, there’s always the 200-night trial to fall back on should you decide it’s not for you. 

Simba Hybrid Ultra Mattress review: Alternatives

Emily Peck

Emily Peck is a lifestyle journalist based in the UK who covers a range of subjects across interiors and design, smart home and gardening, wellbeing and fitness and more. During her 20+ years as a writer she has worked for well-respected magazines and newspapers such as Wired, GQ, Livingetc, Ideal Home, Grand Designs, The Telegraph and TechRadar.