Sleepeezee Cosmic 3000 Combination King Size Mattress
The Sleepeezee Cosmic 3000 Combination Mattress pairs graphite-infused memory foam with micro and pocket springs under a plush pillow top, which means a soft-feeling surface that works to keep heat away.
- Cooler sleep with graphite foam
- Plush pillow top cushioning
- Supportive edges, no roll-off feeling
£1,399
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Sleepeezee Cosmic 3000 Combination Mattress
More available sizes
Mattress details
Mattress
Sleepeezee Cosmic 3000 Combination Mattress
Size
Firmness
Construction
Memory Foam
Pocket Spring
Depth (cm)
33
Layers
3
Layer Details
Plush pillow top
A pillow top finished with reinforced edges. It adds cushioning to the surface, and the reinforced edges help the sides feel steadier.
Graphite-infused memory foam
A memory foam infused with graphite, which draws away heat and moisture. That should help you stay cooler through the night.
Micro and pocket springs
Layers of micro and pocket springs, with 3,000 springs in total, though Sleepeezee doesn't give a size. They provide tailored support and cooling comfort underneath the foam.
Layer details from dreams.co.uk product page, November 2026.
Key benefits
- 7.5cm more each than a UK double: Each sleeper gets 75cm here against 67.5cm on a UK double, which means a slightly wider buffer when one of you shifts position in the night.
- Extra length for taller partners: At 200cm long, the UK king adds 10cm over a UK double, so a partner over six foot is less likely to find their feet hanging off the end.
- Edges you can sleep near: The reinforced pillow top edges and edge-to-edge support mean the full 150cm width is usable, which matters most when two people share a bed this size.
- Room for propping and shifting: During pregnancy, or recovering from surgery, the UK king leaves space for extra pillows while a partner keeps their own side clear.
- Cooler for two warm bodies: Two sleepers generate more heat, and the graphite-infused memory foam and Breeze 3D knit cover are designed to draw warmth and moisture away from the surface.
- Check the bed frame first: At 33cm deep, this mattress sits tall, so confirm your king frame and fitted sheets can take that depth before ordering.
This size suits you if...
You share the bed every night and wake each other when one of you rolls over, one of you is over six foot and has been sleeping diagonally on a UK double, or your schedules differ and the early riser needs room to slip out without disturbing anyone.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m once wardrobes are in. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
What size room do I need for a Sleepeezee Cosmic 3000 UK king?
We suggest allowing at least 2.7m x 2.9m for a UK king, with 3.2m x 3.2m feeling comfortable. New build master bedrooms can feel smaller once fitted wardrobes are in, so measure the floor space left over rather than the room itself. Remember the 33cm depth will also make the bed sit higher.
Is a UK king big enough for two people and a dog?
A UK king gives each of you 75cm before the dog arrives, so a medium or large dog that sleeps on the bed every night will eat into that quickly. If the dog is a fixture rather than an occasional visitor, the UK super king gives 90cm each and needs at least 3m x 2.9m.
Sleepeezee Cosmic 3000 king vs super king: which should couples choose?
Both are 200cm long, so taller sleepers get the same length either way. The UK super king is 30cm wider and gives 15cm more each, which helps if you disturb each other badly. The UK king suits rooms under 3m x 2.9m, where a UK super king would leave little space to walk round.
Will a Cosmic 3000 UK king help if my partner keeps waking me?
A UK king gives each of you 7.5cm more than a UK double, so there is slightly more distance between you. Sleepeezee doesn't publish a firmness or motion isolation rating, though, so the extra width is the only change you can count on. If disturbance is severe, consider the UK super king instead.
What bedding fits a 150 x 200cm Sleepeezee Cosmic 3000?
Standard UK king sheets and a 230 x 220cm king duvet fit the 150 x 200cm footprint. Because this mattress is 33cm deep, check the pocket depth on fitted sheets before buying, as shallower ones may struggle to stay on the corners.