Sleepeezee Diamond Ortho King Size Mattress
The Sleepeezee Diamond Ortho is a medium firm pocket sprung mattress with 1000 pocket springs housed in individual cotton pockets.
- Medium-firm support for back sleepers
- Turnable to wear more evenly
- Hypoallergenic fibre fillings
£429
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Sleepeezee Diamond Ortho Mattress
More available sizes
Mattress details
Mattress
Sleepeezee Diamond Ortho Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Orthopaedic
Depth (cm)
24
Layers
3
Layer Details
Cover
A breathable Belgian damask fabric cover, which means air can move through the sleep surface rather than getting trapped. That helps you stay a little cooler through the night.
Comfort Fillings
Soft white fibre fillings made from 100% polyester. These give a gentle cushioned surface over the firmer springs beneath.
Support System
1000 pocket springs, each mounted in its own separate cotton pocket. Because the springs work completely independently, the mattress responds to your shape and reduces movement transferring across the bed.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Proper room for two: At 75cm each, you get 7.5cm more personal space than on a UK double, which means fewer nudged elbows when one of you rolls over.
- Quieter early exits: The 1000 springs sit in separate cotton pockets, so when one of you leaves hours before the other, the getting-up is less likely to be felt across the bed.
- Length for a tall partner: At 200cm long, the UK king adds 10cm over a UK double, so a partner over six foot is far less likely to find their feet at the edge.
- Firm support edge to edge: The medium firm feel stays consistent across the full 150cm width, which suits back sleepers and heavier builds on both sides of the bed.
- Turning is a two-person job: It is double-sided and can be flipped, although a mattress this broad is easier to turn with your partner helping than on your own.
- Fits most master bedrooms: We suggest a room of at least 2.7m x 2.9m, a slightly smaller footprint than a UK super king asks for.
This size suits you if...
You share the bed every night and feel squeezed on a UK double, one of you finds 190cm too short, or your sleep gets broken when your partner rises before you do.
Consider another size if...
You still want more space each after sizing up, or a dog regularly claims the middle. We'd recommend the UK super king instead, which gives 90cm each; we suggest at least 3m x 2.9m for the UK super king.
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FAQ's
Is the Sleepeezee Diamond Ortho UK king big enough for two people?
For most couples, yes. The UK king gives 75cm each, compared with 67.5cm each on a UK double. The pocket springs also move independently, so your partner turning over is less likely to disturb you. If you want a lot more room than that, look at the UK super king.
Should I get the Sleepeezee Diamond Ortho in a UK king or a UK super king?
The UK king gives 15cm less each than the UK super king, and the two sizes are the same length. We suggest at least 2.7m x 2.9m for the UK king and at least 3m x 2.9m for the UK super king. If your room is tight, the UK king is the easier fit.
Is the Sleepeezee Diamond Ortho UK king long enough for tall sleepers?
At 200cm (6ft 6in), the UK king is 10cm longer than a UK double. That extra length gives a partner over six foot more room at the foot of the bed. You would gain no extra length by moving to the UK super king, because it is the same length.
How hard is it to flip a king size Sleepeezee Diamond Ortho?
Sleepeezee doesn't publish a weight for this mattress. At 150 x 200cm, though, it is a wide, bulky thing to handle alone. Plan to turn it with your partner, lifting from opposite sides. That keeps both faces wearing evenly without anyone straining their back.
Will the Sleepeezee Diamond Ortho UK king fit in a new build bedroom?
We suggest at least 2.7m x 2.9m for the UK king. New build master bedrooms often feel smaller once fitted wardrobes are in, so measure the clear floor space rather than the room plan. If you come up short, the UK double needs at least 2.6m x 2.8m.