Sealy Ortho Support King Size Mattress
The Sealy Ortho Support Mattress is available in five UK sizes, from Single up to Super King.
- Extra-firm feel for a flat surface
- Reinforced edges for more usable space
- Hypoallergenic fibre fillings
£643.50
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Sealy Ortho Support Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Support Mattress
Size
Firmness
Extra Firm
Construction
Orthopaedic
Depth (cm)
Layers
3
Layer Details
PostureTech 2.0 spring core
Sealy's PostureTech 2.0 smart spring core, made up of pocket springs individually encapsulated in fabric, forms the base of the mattress. It gives the firm support you would expect from an extra-firm build.
EdgeGuard surround
EdgeGuard surrounds the spring system and reinforces the sides and edges. That means you get more usable sleep surface, so you can sleep or sit nearer the edge without it feeling weak.
OptiForm extra-firm foam
A double layer of OptiForm extra-firm foam sits on top of the springs and gently cushions and adapts to your body. Expect a firm, fairly flat feel rather than a deep sink-in one.
Layer details from mattressman.co.uk product page, October 2026.
Key benefits
- Proper space for two: At 75cm each for two people sharing, a couple gets meaningfully more personal room than a UK double offers, which you notice most on restless nights.
- Length for taller sleepers: The UK king is 10cm longer than the UK double, which means anyone approaching six foot stops sleeping with their feet at the edge.
- Less disturbance from a partner: With 15cm more width than a UK double, an early riser can slip out with less chance of waking the person still asleep.
- Fits most main bedrooms: We suggest at least 2.7m x 2.9m for a UK king, which most master bedrooms manage without the squeeze a super king can cause.
- Room for a shifting sleeper: During pregnancy or recovery from injury, when you're propping pillows and changing position through the night, the extra width stops every movement travelling to your partner.
This size suits you if...
You share the bed every night and the UK double has started to feel cramped, especially if one of you gets up hours before the other. It also suits you if one partner is tall, since the 200cm length is a genuine relief for anyone near six foot. Couples expecting a baby, or recovering from surgery and needing space to reposition, will feel the extra width every night.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m minimum, or you sleep alone. In either case we'd recommend the Sealy Ortho Support in a UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is the Sealy Ortho Support in a UK king big enough for a couple?
Yes, for most couples it's the comfortable option. A UK king gives 75cm of width each for two people sharing, which is 15cm more overall than a UK double. If one of you moves a lot, sleeps with a dog on the bed, or you're simply tired of negotiating space, this is the size that fixes it.
What room size do I need for the Sealy Ortho Support UK king?
We suggest a room of at least 2.7m x 2.9m for a UK king, so you can walk round the bed and still open wardrobe doors. That's our guidance, not Sealy's. Newer builds can be tighter than they look once furniture goes in, so measure with the wardrobes in place, not the empty room.
Should I get the Sealy Ortho Support in a UK king or UK super king?
The UK king is 30cm narrower than the UK super king, and both are the same 200cm length. If your room meets our suggested 3m x 2.9m minimum for the UK super king and you want maximum space, size up. If space is tighter, the UK king gives couples a real upgrade without dominating the room.
Is a UK king long enough for a tall sleeper?
At 200cm, the UK king is 10cm longer than the UK double, which matters more than width if one of you is around six foot or over. Feet stop hanging near the edge and taller sleepers can stretch out fully. If height is your main frustration with your current bed, length is the upgrade you're paying for.
Where can I buy the Sealy Ortho Support Mattress in a UK king?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them. Because Sealy doesn't publish full firmness or construction details for this model, it's sensible to read the retailer's own listing carefully before ordering, particularly if you have specific back support needs in mind.