Sealy Ortho Plus Gold King Size Mattress
The Sealy Ortho Plus Gold is a firm, double-sided mattress built around Sealy's PostureTech CS springs, which respond to your body weight to give deeper support where you carry the most pressure.
- Extra lumbar support at the centre
- Firm edges, no roll-off feeling
- Double-sided for a longer life
£529
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Sealy Ortho Plus Gold Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Plus Gold Mattress
Size
Firmness
Firm
Construction
Foam
Memory Foam
Orthopaedic
Depth (cm)
29
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 if you tend to run warm at night.
Comfort Fillings
100% polyester fillings that offer good recovery and durability. In practice that means the comfort layer springs back into shape rather than developing body impressions quickly.
Support System
PostureTech CS springs respond to your body weight, targeting key areas to give deep-down support where you need it most. The springs are twice tempered, a heat treatment that helps them keep their tension over time.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Real space for two: At 75cm each for two people sharing, you can change position on a firm surface like this without colliding elbows in the night.
- Less partner disturbance: The PostureTech CS springs respond to each sleeper's weight individually, which means a partner getting up hours before you causes less of a ripple across the wider surface.
- Length for taller sleepers: The UK king is 10cm longer than the UK double, so a partner over six foot gets their feet on the mattress rather than off the end.
- Usable edges on both sides: EdgeGuard foam firms up the perimeter, so with bedside tables on both sides you can each sit or sleep near your own edge without roll-off.
- Turnable at a manageable size: This mattress is double-sided and needs flipping to even out wear, and at 150cm wide a UK king is still a two-person job most couples can manage.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially if one of you gets up much earlier and disturbs the other. Or one of you is tall enough that a 190cm mattress leaves feet hanging, since the extra length matters as much as the width here. It also suits couples who want firm support and enough room that neither drifts into the other's half.
Consider another size if...
Your bedroom is under our suggested minimum of 2.7m x 2.9m, or you sleep alone. In a tighter room we'd recommend the UK double instead, which needs at least 2.6m x 2.8m and still gives a couple a proper shared bed.
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FAQ's
Is a UK king Sealy Ortho Plus Gold good for couples?
Yes, and it's the size most sharing couples end up choosing. You get 75cm each for two people sharing, and because the PostureTech CS springs respond to body weight where each of you lies, movement on one side transfers less to the other. If one of you leaves for work hours before the other, that matters.
Will the Sealy Ortho Plus Gold UK king suit a tall sleeper?
The UK king measures 150 x 200cm, and that 200cm length is 10cm longer than the UK double. For anyone approaching or over six foot, that stops feet hanging off the end, which on a firm mattress like this is particularly noticeable. Height is often the real reason to size up, rather than width.
What room size do I need for a king mattress?
We suggest at least 2.7m x 2.9m for a UK king. New build master bedrooms can be tighter than they first appear once fitted wardrobes go in, so measure the finished floor space rather than the plan. If your room falls short, the UK double needs at least 2.6m x 2.8m.
Is a UK king hard to flip on your own?
The Ortho Plus Gold is double-sided and designed to be turned, which extends its life. A UK king is 5ft x 6ft 6in, so treat flipping as a two-person job. If you live alone and would struggle, that's a reason to consider the UK double, which is 15cm narrower and 10cm shorter.
Should I get the UK king or the UK super king Sealy Ortho Plus Gold?
The UK super king is 30cm wider than the UK king and the same length, so it adds elbow room rather than legroom. If a dog routinely claims part of the bed, or you both want more personal space, size up, but allow at least 3m x 2.9m of room for the UK super king. Otherwise the UK king suits most couples.