Sealy Ortho Plus Bronze Super King Mattress
The Sealy Ortho Plus Bronze is an extra firm sprung mattress built for people who want proper orthopaedic support rather than a soft, sink-in feel.
- Extra-firm support
- Stable edges, no roll-off feeling
- Double-sided to spread the wear
£599
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Sealy Ortho Plus Bronze Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Plus Bronze Mattress
Size
Firmness
Extra Firm
Construction
Foam
Orthopaedic
Depth (cm)
28
Layers
4
Layer Details
Knitted Cover
A soft knitted cover that's breathable, which means heat can escape rather than build up. It helps keep you at an even temperature through the night.
Soft White Fibres
Fibre fillings made from 100% polyester, chosen for recovery and durability. In practice that means the comfort layer springs back rather than flattening quickly.
PostureTech CS Springs with EdgeGuard
The PostureTech Core Support spring system responds to changes in your sleeping position, targeting support where you need it most. Each spring holds an EdgeGuard high-density foam insert, which strengthens the mattress edges and extends the springs' lifespan.
PowerPack Core
The PowerPack at the core works with the PostureTech system to keep your lumbar region comfortable and safely aligned. It's the layer doing the deep support work for your lower back.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- 90cm of width each: Two people sharing get 90cm each, which means a partner who shifts position all night is far enough away that you barely register it.
- Extra firm support across the full 180cm: The PostureTech CS springs and PowerPack core keep the surface consistently supportive edge to edge, so nobody drifts into a soft middle.
- EdgeGuard makes the outer inches usable: Each spring carries a high-density foam insert that firms up the sides, useful when a child or dog pushes you towards the edge overnight.
- Double-sided wear at family scale: Both faces carry fillings, so a mattress taking the weight of two adults plus occasional visitors can be turned to spread the wear evenly.
- Breathable knitted cover: The knitted cover lets heat escape rather than trap it, which matters more when several warm bodies end up sharing one surface.
This size suits you if...
You share every night and want the most sleeping space a standard UK size offers, your partner is genuinely restless and distance matters more to you than any comfort layer, or children and pets regularly find their way in and everyone still needs a firm, supportive stretch of their own. Your bedroom should comfortably clear our suggested minimum of 3m x 2.9m.
Consider another size if...
Your room falls short of the 3m x 2.9m we suggest for a UK super king, or you'd struggle to turn a mattress this size regularly. We'd recommend the UK king instead: it's 30cm narrower, the same length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
How big is the Sealy Ortho Plus Bronze in a UK super king?
It measures 180 x 200cm, which is 6ft x 6ft 6in. That makes it 30cm wider than the UK king and the same length, so you gain width for two sleepers without needing a longer room. Two people sharing get 90cm each.
Is the Sealy Ortho Plus Bronze super king hard to turn?
It needs regular turning, since it's double-sided with fillings on both faces, and at 180cm wide this is realistically a two-person job. If nobody in the house can help with flipping, a smaller size, or a different mattress entirely, may be more practical.
Is a super king Sealy Ortho Plus Bronze good for a restless partner?
It's one of the better pairings for this. The 90cm each of width puts real distance between you, and the extra firm PostureTech CS spring system keeps the surface stable rather than bouncy, so movement on one side is less noticeable on the other.
What room size do I need for the Sealy Ortho Plus Bronze in a super king?
We suggest at least 3m x 2.9m, with around 3.5m x 3.2m feeling more comfortable. That's our guidance rather than Sealy's. In a large master or a period property with generous proportions, a UK king can look undersized, and the super king fills the space properly.
Can children share the Sealy Ortho Plus Bronze super king with us?
It suits that situation well. With 180cm of width, a child wandering in at night doesn't leave anyone clinging to the edge, and the EdgeGuard foam inserts firm up the sides so the outer inches stay supportive rather than sloping away. The extra firm surface stays stable under the extra weight.