Sealy Ortho Plus Essential King Size Mattress
The Sealy Ortho Plus Essential is a medium firm sprung mattress from a long-established brand.
- Firm-leaning support
- Twice-tempered springs resist dipping
- Damask cover lets air move through
£399
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Sealy Ortho Plus Essential Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Plus Essential Mattress
Size
Firmness
Medium Firm
Construction
Foam
Memory Foam
Orthopaedic
Open Coil Spring
Depth (cm)
27
Layers
3
Layer Details
Damask Cover
A cover made from breathable Belgian damask fabric, which means air can move through the sleep surface rather than getting trapped against you. It gives a traditional, tailored finish.
Soft White Fibres
Soft fibre fillings made from 100% polyester sit above the springs. They add a slightly softer initial feel before you reach the firmer support beneath.
PostureTech CS Springs
These springs respond to your body weight to provide deep down support, so heavier areas like hips and shoulders get pushed back where needed. They are twice tempered, which means the steel is treated to stay resilient 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 both change position without negotiating, which matters on a firmer surface where you tend to move more.
- Extra length for taller sleepers: The UK king is 10cm longer than the UK Double at 200cm, so a partner over six foot stops waking with their feet off the end.
- Firm support across the full width: The PostureTech CS springs respond to body weight, so a heavier and lighter partner each get support suited to them rather than a shared compromise.
- Distance softens the open coil trade-off: Open coil designs transfer more movement than pocket springs, but the extra width puts more mattress between you, which takes some sting out of a partner's early alarm.
- Breathable surface for shared heat: Two people warm a bed faster than one, and the Belgian damask cover lets air move through the surface rather than trapping it.
This size suits you if...
You share the bed every night and the double has started to feel like a negotiation, or one of you is approaching six foot and needs the 200cm length as much as the width. It also suits couples on mismatched schedules who want more distance between them, since a firmer open coil mattress passes on more movement than pocket springs and the extra width helps offset that.
Consider another size if...
Your bedroom is under our suggested 2.7m x 2.9m minimum, common in newer builds once wardrobes go in. We'd recommend the UK double instead, which needs around 2.6m x 2.8m and still gives a couple a workable night.
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FAQ's
Is the Sealy Ortho Plus Essential in a UK king big enough for two adults?
Yes, comfortably for most couples. The 150cm width gives 75cm each for two people sharing, and the medium firm PostureTech springs support each sleeper's weight independently across that width. If one of you is a restless sleeper, the extra room helps, though the open coil design still transfers more motion than pocket springs would.
Will a UK king fit in a smaller master bedroom?
We suggest at least 2.7m x 2.9m for a UK king, and that minimum gets eaten quickly by fitted wardrobes in a newer build. Measure with the doors open and walking space in mind. If the room falls short, the UK double needs around 2.6m x 2.8m and is a safer fit.
Is the UK king long enough for someone over six foot?
At 200cm, or 6ft 6in, it gives a sleeper over six foot proper clearance at the head and foot. That extra 10cm over the UK double is often the difference between feet hanging off the base and a full stretch, and on a firmer sprung mattress like this you notice the edge more.
Should a couple choose the UK king or the UK super king for this mattress?
The UK super king is 30cm wider than the UK king, the same length, and we suggest at least 3m x 2.9m of room for it. If partner disturbance is your main worry, that extra width helps most with this open coil design. For most bedrooms and budgets, though, the UK king is the sensible middle ground.
How do I get the best price on the Sealy Ortho Plus Essential in a UK king?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so what you see reflects the current UK king price rather than a snapshot. Mattress pricing moves around sales periods, so it can pay to check back before ordering.