Arthur Sleep Cool Comfort King Size Mattress
The Arthur Sleep Cool Comfort is a pocket spring mattress that pairs its springs with advanced cooling foams, which means the foam layer is designed to draw heat away rather than trap it against you.
- Cooling foams for warm sleepers
- Minimises partner disturbance
- Classic pocket spring feel
£409
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Arthur Sleep Cool Comfort Mattress
More available sizes
Mattress details
Mattress
Arthur Sleep Cool Comfort Mattress
Size
Firmness
Medium
Construction
Pocket Spring
Depth (cm)
Layers
5
Layer Details
Gel foam
A cooling gel foam sits at the top to counteract the heat retention of memory foam and keep the surface breathable. If you tend to overheat, this is the layer that matters most.
Memory foam
Memory foam works with the gel layer above it to give body-cradling comfort. You get that gentle, sink-in contouring, with the gel there to take the edge off the warmth.
Comfort foam
A dense layer of eco-high resistance PU foam that gives a soft, cushiony feel. It adds support beneath the softer layers above, so the top doesn't feel too sinky.
Convoluted foam
High resilience convoluted foam spreads your body weight evenly for targeted pressure relief. It should help the mattress ease off heavier areas such as hips and shoulders.
Encased foam edge
A 10cm encased foam structure surrounds the pocket springs for extra support and stability. It should make the sides feel steadier when you sit on the edge or sleep close to it.
Layer details from arthursleep.co.uk and mattressman.co.uk product pages, October 2026.
Key benefits
- Proper space for two: At 75cm each for two people sharing, you can both change position without negotiating, which matters most with the cooling foams doing their work overnight.
- Less disturbance on different schedules: Pocket springs compress independently, so if one of you leaves for work hours before the other, the movement is far less likely to travel across the bed.
- Length for taller sleepers: The UK king is 10cm longer than the UK double at 200cm, a genuine relief if either of you is approaching or past six foot.
- Room for the dog too: If a pet claims the foot of the bed most nights, the UK king's 5ft x 6ft 6in footprint absorbs that habit without one of you losing out.
- Cooling where it counts: Two bodies generate more heat than one, so the heat-drawing foam layer is arguably more useful in a shared UK king than in a smaller size.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially if one of you keeps earlier hours and you want their alarm to pass you by. It also makes sense if either partner is tall, since the extra 10cm of length over a UK double is the difference between feet on the mattress and feet off the end.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case the UK double would suit you better, needing a slightly smaller room of at least 2.6m x 2.8m.
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FAQ's
Is the Arthur Sleep Cool Comfort in a UK king big enough for a couple?
Yes, comfortably for most. The UK king measures 150 x 200cm, giving 75cm each for two people sharing. The pocket springs also move independently, so a restless partner disturbs you less. If one of you is broad-shouldered or you both spread out, the UK super king adds another 30cm of width.
Will a UK king Arthur Sleep Cool Comfort fit my bedroom?
We suggest a room of at least 2.7m x 2.9m for a UK king, which leaves space to walk round the bed and open drawers. New build master bedrooms can be tighter than they look once fitted wardrobes go in, so measure the usable floor rather than the room on the plan.
Should I get the Arthur Sleep Cool Comfort in a UK king or a UK double?
For couples, the UK king is usually the better buy. It is 15cm wider and 10cm longer than the UK double, and with the cooling foams handling the extra warmth of two sleepers, the added width means fewer accidental elbows. Solo sleepers or those with smaller rooms are better served by the UK double.
Is the UK king long enough for someone over six foot?
At 200cm, or 6ft 6in, the UK king gives a tall sleeper more length than the UK double, which is 10cm shorter. For anyone whose feet hang off a standard mattress, this length is often the real reason to size up, more so than the width.
Which size of this mattress is best for reducing partner disturbance?
The UK king is the sensible starting point. Its 75cm each for two people sharing, combined with pocket springs that compress independently, keeps most of a partner's movement on their side. Very light sleepers, with the room for it, could consider the UK super king, which is 30cm wider and needs at least 3m x 2.9m.