SleepSoul Space Ortho Memory Pocket 4000 Boxtop King Size Mattress in a Box
The SleepSoul Space Ortho Memory Pocket 4000 Boxtop is a firm, deep 38cm hybrid mattress delivered vacuum-packed in a box.
- Firm, finely responsive support
- Minimises partner disturbance
- 10-year guarantee
£517.76
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SleepSoul Space Ortho Memory Pocket 4000 Boxtop Mattress in a Box
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Mattress details
Mattress
SleepSoul Space Ortho Memory Pocket 4000 Boxtop Mattress in a Box
Size
Firmness
Firm
Construction
Foam
Pocket Spring
Hybrid
Rolled
Memory Foam
Depth (cm)
38
Layers
7
Layer Details
Top Layer
A sumptuously soft pillow-top layer of plush filling sits right at the surface. This gives extra cushioning before you reach the firmer support below.
Tencel Knitted Top Fabric
The knitted cover is made from Tencel, a soft, breathable fabric. It helps the surface stay cooler through the night.
Foam Layer
A 1cm foam layer paired with 3.5cm of memory foam offers two levels of comfort and support. The memory foam element moulds gently to your shape.
Cool Gel / Memory Foam
3.5cm of cool gel acts as a transition layer, which means a controlled sink rather than a sudden drop, with movement kept to a minimum. The memory foam contours to your body and eases pressure points.
Mini Pocket Springs
An additional 2000 mini pocket springs sit above the main spring unit. These add a finer level of comfort and support close to the surface.
Pocket Springs
2000 pocket springs conform to your body's shape, supporting you where you need it most. Because each spring moves independently, they help prevent the roll-together effect on a shared bed.
Base
A non-slip fabric base adds stability. It helps keep the mattress in place on your bed frame.
Layer details from sleepsoul.co.uk product page, September 2026.
Key benefits
- More room each: Moving up from a UK double gives each of you 7.5cm more width, so an elbow or a turn in the night is less likely to reach your partner.
- Length for taller partners: At 200cm long, the UK king is 10cm longer than a UK double, so a tall partner's feet are less likely to hang over the end.
- Quieter for split schedules: Independent pocket springs and memory foam limit how far movement spreads, which helps when one of you gets up hours before the other.
- Space to prop and shift: A 150cm width leaves room for a pregnancy pillow or extra support cushions without pushing the other sleeper towards the edge.
- Fits more bedrooms than a super king: We suggest at least 2.7m x 2.9m for the UK king, compared with 3m x 2.9m for the UK super king.
This size suits you if...
You share the bed every night and your UK double now feels cramped, or one of you is tall and often ends up with feet past the end. It also suits you if your partner keeps different hours and you want a firm mattress that keeps their movement on their own side.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m once wardrobes are in. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is the SleepSoul Space Ortho UK king big enough for two people?
Yes, for most couples. The UK king gives 75cm each when two share, which is 7.5cm more per person than the UK double. If a dog regularly sleeps on the bed too, space can still feel tight, and the UK super king's 90cm each may suit you better.
Is the SleepSoul Space Ortho long enough for a tall person in a UK king?
The UK king is 200cm (6ft 6in) long, 10cm longer than a UK double. If one of you is tall, this extra length can matter more than the extra width, because it reduces the need to sleep diagonally.
Will my partner's movement disturb me on the SleepSoul Space Ortho UK king?
Across the 150cm width, each of you has 75cm of your own. The individually moving pocket springs and the memory foam and gel layers are designed to limit how far movement travels, which helps if one of you gets up early or turns over often.
Should I choose the UK king or UK super king SleepSoul Space Ortho?
The UK king is 30cm narrower than the UK super king and gives 15cm less each, but both are the same length. We suggest at least 2.7m x 2.9m for the UK king and 3m x 2.9m for the UK super king, so your room size often decides it.
What size bedroom do I need for a SleepSoul Space Ortho UK king?
We suggest at least 2.7m x 2.9m. At 38cm deep, the mattress also sits tall on its frame, so if getting in and out is harder after an injury, leave clear floor space on both sides.