The best king size mattresses you can buy in 2024
Sleep like a king with the best mattresses from Emma, Simba and more
Struggling to catch forty winks in a bed that’s too small? The best king size mattress can provide you with plenty of room to get a great night’s sleep. If you share a bed with a partner, or you just value your space, a king size mattress can be a welcome upgrade from a double.
With a dizzying array of mattresses available, many of which you can now get rolled up and delivered to your door in a box, trying to find the right mattress for your personal preferences is a task in itself. And if you do sleep with a partner, you’ve got the sleeping habits of two people to take into consideration. It’s enough to make you want to lie down.
However, having tested and reviewed a wide range of mattresses, we promise to bring you the most informed buying advice possible. We’ve put together the following roundup, featuring some of our favourite mattresses to buy in a king size.
READ NEXT: Best mattresses
Best king size mattress: At a glance | ||
|---|---|---|
| Best memory foam mattress for couples | Emma NextGen Premium | Check price at Emma |
| Best hybrid mattress | Simba Hybrid Pro | Check price at Simba |
| Best for reducing motion transfer | Eve Premium Hybrid | Check price at Eve |
| Best budget hybrid | Nectar Essential Hybrid | Check price at Nectar |
How to choose the best king size mattress for you
How big is a king?
A standard king size mattress measures 150cm by 200cm, while a double mattress measures 135 by 190cm. It goes without saying that, if you’re upgrading from a double mattress, you should make sure you have enough space to accommodate a king size.
It’s also worth mentioning that king size mattresses are 10cm longer than singles and doubles, so you might want to invest in a king if you’re especially tall.
READ NEXT: The best mattress toppers to buy
How we test mattresses
It’s probably pretty obvious, but we test our mattresses by sleeping on them. While it might sound somewhat straightforward, there are also a number of key factors we take into account. With the inclusion of comfort and support, we place focus on temperature control and firmness – though with some mattresses we will also consider edge support and motion isolation.
When looking at temperature control, all-foam mattresses will feel warmer than other models, making them less suitable for those susceptible to overheating at night.
We also consider the base on which you put your mattress – whether it be a hard divan base, sprung slatted bed or even the floor – it will affect how the mattress feels beneath you. And though we can’t always test a selection of bed bases when reviewing a mattress, we will always consider this in our final decision.
Following our initial tests, we consider any trial runs that might be available – which is often the case with the bed-in-a-box market – before asking the all-important question, is the product good value for money?
Regardless of whether you’re after a single, double or king size, we recommend checking out our dedicated mattress buying guide, as well as some of the other pages listed below:
The best king size mattresses you can buy in 2024
1. Emma NextGen Premium: Best king size mattress for couples
Price when reviewed: £809 | Check price at Emma
Emma’s premium mattress has gradually fallen in price since it launched at the height of summer 2023, and you can now snap up a king size for £809 – and that’s before you take into account Emma’s occasional discount sales. What hasn’t changed, though, is the superb balance of cosy comfort, pressure-relieving support and breathability that so impressed us when we tested it.
Thanks to an innovative combination of large, super-supportive pocket springs and assorted layers of foam, the Emma NextGen Premium achieves a rare feat among hybrid mattresses: it keeps you cool, even if you usually tend to get warm in bed. Its motion isolation is also excellent, so it should make nighttime a lot more peaceful if you or your partner tend to sleep restlessly.
Read our full Emma NextGen Premium review
| Key features | |
| Type | Foam and pocket spring hybrid (185mm “extra tall” springs, 140mm high-resistance polyurethane foam, 200mm visco-elastic memory foam) |
| Needs turning? | No |
| Sizes | Five sizes from single to super-king |
| Warranty | 200-night trial, 10-year warranty |
2. Simba Hybrid Pro: Best king size hybrid mattress
Price when reviewed: £1,329 | Check price at Simba
One of our very favourite hybrids, the Hybrid Pro sits in the middle of Simba’s mattress range (between the regular Hybrid and the Hybrid Luxe). It’s constructed from a combination of foam, two layers of micro pocket springs and an upper comfort layer made from British wool (which also helps you stay cool during the night).
The king size Hybrid Pro costs a fair bit at £1,749. However, it’s worth pointing out that, like most bed-in-a-box mattresses, you get a lengthy trial period (200 nights), at the end of which you can return it for a full refund if you’re not happy with it. Besides, we would argue that a mattress this comfortable and supportive is well worth its price tag.
Read our full Simba Hybrid Pro review
| Key features | |
| Type | Wool, foam and micro pocket spring hybrid |
| Needs turning? | Rotate once/month for the first six months; once every 3/6 months thereafter |
| Sizes | Single to king |
| Warranty | 10-year warranty, 200-night trial with money-back guarantee |
3. Nectar Essential Hybrid mattress: Best budget king size hybrid mattress
Price when reviewed: £650 | Check price at Nectar
Nectar’s Essential Hybrid undercuts many of its bed-in-a-box rivals on price, making this 25cm thick six-layer mattress one of the cheapest hybrids we’ve reviewed. Our tester found this medium-firm mattress offered comfort and support in excellent measure, as well as good motion isolation to give you some peace from a fidgety sleeping partner. Its edge support could be stronger, but if you’re opting for king size you’re unlikely to be squeezed right to the edge of the bed anyway.
Best of all, Nectar’s trial period and warranty are unbeatable. Not only do you get a full year to sleep on your mattress before deciding whether to keep it, but you also get a free lifetime (actually, “forever”) guarantee against faults. So if you’re looking for a forever mattress, this could be the one.
Read our full Nectar Essential Hybrid review
| Key features | |
| Type | Foam and pocket spring hybrid with six layers, including dynamic support layer, pressure relieving foam, encapsulated 15cm pocket springs |
| Needs turning? | No |
| Sizes | Five sizes from single to super-king |
| Warranty | 365-night trial, forever warranty |
4. Eve Premium Hybrid: Best king size mattress for motion transfer
Price when reviewed: £1,449| Check price at Eve
Of Eve’s extensive mattress range (the bed-in-a-box brand has no fewer than six foam and hybrid mattresses), we found the Premium Hybrid to be the best. Like the Emma Original, it’s a great choice for couples, largely thanks to its ability to reduce motion transfer. This means that you can sleep soundly even when your partner is tossing and turning during the night.
Beyond this, the Premium Hybrid strikes an excellent balance between comfort and support. Eve also recently extended its mattress trial period from 100 nights to 365 nights, meaning you can try it for a full year and return it for a full refund if it’s not the right one for you.
Read our full Eve Premium Hybrid review
| Key features | |
| Type | Foam and pocket spring hybrid |
| Needs turning? | Rotate once every month or so |
| Sizes | Double to super king |
| Warranty | 10-year warranty, 365-night trial period with money-back guarantee |
5. Origin Hybrid mattress: Best supportive king size mattress
Price when reviewed: £629 | Check price at Origin
Origin’s Hybrid mattress gives you the optimum balance of comfort and ergonomic support right across the sleeping surface, from edge to edge. If you share your king size bed, this consistent support maximises the amount of comfort you can both enjoy, rather than having it taper off as you move towards the edge of the mattress.
Like many newer hybrid mattresses, the Origin Hybrid features a grid layer that’s designed to optimise back support, plus a temperature-control layer to keep you cool while you sleep. There’s also a solid foam layer for extra support where it’s needed, and a layer of pocket springs whose innovative design offers better and better support the further you sink into the mattress.
Read our full Origin Hybrid mattress review
| Key features | |
| Type | Hybrid with six layers, including “HexaGrid” foam, bamboo-infused wool, cooling cover, 3,000 pocket springs |
| Needs turning? | No |
| Sizes | Five sizes from single to super-king |
| Warranty | 200-night trial, 15-year guarantee |
6. Hypnia Supreme: Best luxurious king size hybrid mattress
Price when reviewed: From £1,625 | Check price at Hypnia
While all-foam mattresses can be great for side sleepers because they have plenty of “give” for the contours of your hips and shoulders, they sometimes lack the ergonomic support and durability you also need for a proper night’s rest. Not so with this premium mattress from Hypnia, which offers a superb level of support from edge to edge.
Supreme by name, Supreme by nature – and Supreme by price too, as this mattress is certainly an investment, with a king size costing £1,625 when it’s not being treated to one of Hypnia’s fairly regular discounts. However, it does feel like a mattress that will last for many years without sagging, and it comes with a generous 15-year guarantee from Hypnia – that works out to little more than £100/yr, which isn’t a bad deal for such a supremely comfortable sleep.
Read our full Hypnia Supreme review
| Key features | |
| Type | Foam with four layers, including premium memory foam, graphite-infused open-cell foam, multi-zoned support base |
| Needs turning? | No |
| Sizes | Five sizes from single to super king |
| Warranty | 200-night trial, 15-year guarantee |
7. Tempur Original Supreme: Best premium king size foam mattress
Price when reviewed: £1,750 | Check price at Bensons for Beds
It may be the priciest mattress on our rundown, but if you’re looking for a memory foam mattress and you don’t want to compromise, there’s nothing quite like the Tempur Original Supreme. This mattress has a unique feel that most of its new-age bed-in-a-box rivals can only aspire to. Its upper layers of foam give relief to your hips and shoulders, while its lower layers provide ample support for your lower back, and the overall effect is one of supreme comfort without sacrificing support.
There’s no denying it’s a considerable outlay, but if the Tempur Original Supreme helps you sleep at night and be pain-free during the day, then it may well be an investment worth making.
Read our full Tempur Original Supreme review
| Key features | |
| Type | Memory foam with three layers, including 1100mm Durabase, 80mm support foam, 20mm comfort foam |
| Needs turning? | No |
| Sizes | Five sizes from single to super king |
| Warranty | 40-night trial if bought from Bensons for Beds, 10-year guarantee |