Sealy Ortho Plus Silver Memory King Size Mattress
The Sealy Ortho Plus Silver Memory Mattress pairs a memory foam comfort layer with Sealy's PostureTech CS spring system, which means you get body-shaping pressure relief on top with responsive support underneath.
- Memory foam eases pressure points
- Support that follows how you move
- Firmer edges for sitting & dressing
£479
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Sealy Ortho Plus Silver Memory Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Plus Silver Memory Mattress
Size
Firmness
Medium Firm
Construction
Memory Foam
Depth (cm)
25
Layers
2
Layer Details
MemorySense Foam PowerPack
A comfort layer that adapts to the shape of your body, cocooning you in soft foam. It relieves pressure on the parts of your body that bear the majority of your weight, typically hips and shoulders.
PostureTech CS Spring System with EdgeGuard
Sealy's adaptive spring system responds to subtle shifts in body weight and pressure, giving localised support rather than a uniform push-back. High-density EdgeGuard foam strips wrapped around the inside of the springs firm up the edges of the bed.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Room to sleep apart, together: At 75cm each for two people sharing, you can both settle into the memory foam without ending up in each other's space.
- Less partner disturbance: The PostureTech CS springs respond to movement locally, and the wider UK king puts more mattress between you, helpful if one of you gets up hours earlier.
- Extra length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, a genuine relief if either of you is approaching six foot.
- Usable edges across the full width: EdgeGuard foam firms up the perimeter, so the space near the sides of a 150cm-wide bed is sleepable rather than a soft drop-off.
- Check your access route: This mattress arrives flat rather than rolled, and a 150 x 200cm mattress needs a clear path up stairwells and around landings, so measure before ordering.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially if one of you is a restless sleeper or keeps different hours. It also makes sense if either partner is tall, since the 200cm length removes that feet-over-the-end problem, or if a dog has quietly become a permanent third occupant and you want your share of the mattress back.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest for a UK king, or your staircase can't take a flat-delivered mattress this size. The UK double needs only 2.6m x 2.8m and would suit you better.
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FAQ's
Is the Sealy Ortho Plus Silver in a UK king good for couples?
Yes, and it's arguably the size this mattress works best in for two people. You get 75cm each for two people sharing, and the PostureTech CS springs keep support localised rather than tilting the whole surface, so an early alarm on one side is less likely to wake the other.
How much bigger is the UK king than the double in this mattress?
The UK king is 15cm wider and 10cm longer than the UK double. The width is what you notice night to night as a couple, while the extra length helps anyone approaching six foot sleep without their feet reaching the end of the memory foam surface.
What room size do I need for the Sealy Ortho Plus Silver king?
We suggest at least 2.7m x 2.9m for a UK king, which is our guidance rather than Sealy's. That allows space to walk around the bed and open drawers. In a new build master bedroom, measure after accounting for wardrobes, as fitted furniture eats floor space quickly.
Will a UK king Sealy Ortho Plus Silver fit up my stairs?
It needs checking, because this mattress is delivered flat rather than rolled and boxed, and at 150 x 200cm it's an awkward shape to manoeuvre. Measure your doorways, stairwell and any tight turns on the route to the bedroom before you order, particularly in older houses with narrow landings.
Should I get the king or super king in this mattress?
The UK king is 30cm narrower than the UK super king, and the two are the same length. If your room comfortably exceeds the 3m x 2.9m we suggest for a UK super king and you want maximum personal space, size up. Otherwise the UK king is the easier fit.