SleepSoul Space 4000 Orthopaedic Super King Mattress
The SleepSoul Space 4000 Orthopaedic Mattress is a pocket spring design with 4,000 springs, which means each spring can respond to your body independently rather than the whole surface moving as one.
- Firm feel for back & front sleepers
- CoolGel foam helps you sleep cooler
- Non-slip base stays put on frames
£638.10
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SleepSoul Space 4000 Orthopaedic Mattress
More available sizes
Mattress details
Mattress
SleepSoul Space 4000 Orthopaedic Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Orthopaedic
Depth (cm)
Layers
6
Layer Details
Soft cover
A knitted cover, which another page describes as Tencel. It's the surface you lie on, so it gives the mattress a smooth, soft first touch.
Memory foam
A 1cm layer of memory foam. It's thin, so it adds a little cushioning under your body without taking away the firm feel.
CoolGel foam
A 3.5cm layer of CoolGel foam. It's the thickest foam layer here and adds comfort over the springs, with the gel aimed at keeping the surface from feeling too warm.
Mini pocket springs
A layer of 2000 mini pocket springs. Each one moves on its own, so the surface can follow your shape more closely under the foam.
Support pocket springs
A layer of 2000 support pocket springs that forms the core. It carries your weight and keeps you held level, which gives the mattress its firm, supportive base.
Non-slip base fabric
A non-slip underside made for bedframes and ottomans. It helps the mattress stay where you put it, so it doesn't creep around on the base.
Layer details from mattressman.co.uk and mattressonline.co.uk product pages, October 2026.
Key benefits
- Distance from a restless partner: At 90cm each, you get 15cm more than you would each have on the UK king, which means an outflung arm or a sudden turn is far less likely to wake you.
- Movement stays on one side: The 4,000 pocket springs work independently, so when someone gets up in the small hours the dip stays under them rather than rolling across the bed.
- Room when the children climb in: A small child who wanders in at night can take the middle without pushing either adult to the edge, and nobody ends up decamping to the spare room.
- Space for a dog that shares: If a large dog sleeps on the bed as a matter of routine, the extra 30cm over the UK king gives it somewhere to stretch out that isn't across your legs.
- Length for taller sleepers: At 200cm long, which is 10cm longer than the UK double, taller sleepers can lie fully stretched out without their feet ending up over the edge.
This size suits you if...
You and a partner keep disturbing each other on anything smaller, children or a large dog regularly end up in the bed with you, and your bedroom comfortably clears our suggested minimum of 3m x 2.9m.
Consider another size if...
Your bedroom is smaller than 3m x 2.9m, or a tight landing and door swing leave little clearance. We'd recommend the UK king instead, for which we suggest at least 2.7m x 2.9m.
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FAQ's
Is the SleepSoul Space 4000 super king big enough for two adults and a child?
For occasional night visits, yes. The UK super king is 180cm wide, giving two adults 90cm each before a child arrives, so a small one can usually settle in the middle without anyone clinging to the edge. If an older child sleeps in with you every night, space will feel tighter, though still more generous than any smaller size of this mattress.
SleepSoul Space 4000 super king or king: which should I choose?
The UK super king is 30cm wider than the UK king and the same length, giving each of you 15cm more width. That extra width matters most if one of you is restless or children and pets join you. The trade-off is room: we suggest at least 3m x 2.9m for the UK super king against 2.7m x 2.9m for the UK king.
How much bigger is the SleepSoul Space 4000 super king than the double?
The UK super king is 45cm wider and 10cm longer than the UK double. For two people sharing, the UK double gives 67.5cm each, so the UK super king gives 22.5cm more each. It needs more floor space, though. We suggest at least 2.6m x 2.8m for the UK double and at least 3m x 2.9m for the UK super king.
Does a super king help with a partner who tosses and turns?
It helps more than any comfort layer could. On the SleepSoul Space 4000, the 4,000 independent pocket springs keep much of a partner's movement on their side. The UK super king then adds physical distance, with 90cm each, so fidgeting has further to travel before it reaches you. If disturbance is your main complaint, this is the size to choose.
Is the super king the largest size of the SleepSoul Space 4000?
Yes. The SleepSoul Space 4000 is listed in UK double, UK king and UK super king, so the UK super king at 180 x 200cm, or 6ft x 6ft 6in, is as large as it goes. The prices shown on this page update as retailers change them, so compare the listings here before you buy.