Harrison Spinks Platinum 12500 Pocket Super King Mattress (Soft to Medium Feel)
The Harrison Spinks Platinum 12500 is a soft to medium pocket spring mattress, handcrafted in the UK from natural fibres including British wool, cotton, hemp and flax.
- Pressure relief suited to side sleepers
- Wool regulates temperature naturally
- Support builds as you sink in
£2,299
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Harrison Spinks Platinum 12500 Pocket Mattress (Soft to Medium Feel)
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Mattress details
Mattress
Harrison Spinks Platinum 12500 Pocket Mattress (Soft to Medium Feel)
Size
Firmness
Medium Soft
Construction
Pocket Spring
Wool
Natural
Depth (cm)
29
Layers
5
Layer Details
Comfort Layer
Plush British wool sits at the top, which means natural temperature regulation. Wool wicks moisture, so you stay cosy in winter and cooler in summer.
Comfort Blend
Cotton and wool fibres are blended with hemp and flax. These tougher plant fibres help the comfort layers keep their shape over time.
Sustainable Layer
A layer of Ecotex fibres made from recycled materials. It's there for strength and durability rather than softness.
Support System
10,500 mini springs contour closely to your body, backed by 1,000 Posturfil springs that flex with your movements and weight distribution. This is where the personalised, cradling feel comes from.
Spring System
At the base, 1,000 Cortec Quad Revolution springs sit in individual pockets, secured in groups of four, with a mini spring inside each one. That layered spring-within-a-spring design gives progressive support as you sink in.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- 90cm each, every night: Two people sharing get 90cm apiece, which means a partner who turns often is simply further away and much easier to ignore.
- Springs, not motion transfer: The 12,500-spring build responds to each sleeper individually, so movement on one side stays largely on that side, a real advantage across this width.
- Room for the whole household: At 6ft x 6ft 6in there's space when children or a large dog treat your bed as theirs, without anyone hanging off an edge.
- Wool keeps a big bed temperate: British wool wicks moisture across the full surface, which matters when three bodies and a duvet share one mattress in summer.
- Soft feel at full scale: The gently cushioned, cradling surface suits side sleepers, and in this size two people with different sleep positions can each settle without disturbing the other.
This size suits you if...
You share the bed every night and want the most sleeping space a standard UK size offers, your partner is genuinely restless and distance matters more than any comfort layer, or children and pets regularly join you and everyone still needs their share. Your bedroom should measure at least 3m x 2.9m, with more feeling comfortable.
Consider another size if...
Your room is under our suggested 3m x 2.9m minimum, or the bed would dominate the space. We'd recommend the UK king instead: it's 30cm narrower, the same length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
How big is the Harrison Spinks Platinum 12500 in a super king?
It measures 180 x 200cm, or 6ft x 6ft 6in. Two people sharing get 90cm each, which is the same width per person as a single bed. The mattress itself is 29cm deep, so allow for that when choosing fitted sheets and checking headboard height.
What room size do I need for the Platinum 12500 super king?
We suggest at least 3m x 2.9m, and around 3.5m x 3.2m feels right, leaving space to walk round both sides and open drawers. In a smaller master bedroom the UK king, at 30cm narrower, keeps the room usable. This is our guidance rather than the manufacturer's.
Is a super king worth it for a restless partner?
Often, yes. The extra 30cm over a UK king puts real distance between you, and the Platinum 12500's pocket spring construction responds to each body separately, so movement carries less across the surface. The combination of width and independent springs does more for disturbed sleep than any comfort layer alone.
Will the Platinum 12500 super king get up my stairs?
It's the check that bites most at this size. A 180cm-wide, 29cm-deep pocket spring mattress can't be folded like foam, so measure your stairwell, landing turns and door swings before ordering. If access is tight, the UK king is 30cm narrower and noticeably easier to manoeuvre.
Is the super king big enough for co-sleeping with children?
It's the best standard size for it. With 90cm per adult to start, a child wandering in at night takes a share without pushing anyone to the edge, and the soft to medium surface cushions smaller bodies comfortably. Large dogs sharing as routine are also easier to accommodate at this width.