Hypnos Wool Tranquility King Size Mattress
The Hypnos Wool Tranquility is a medium firm pocket sprung mattress built around natural fibres: sustainably sourced British wool and cotton over 1400 of Hypnos's ReActive 8-turn pocket springs.
- Less clammy than all-foam beds
- Hips sink in, shoulders stay supported
- Suits back & combination sleepers
£949
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Hypnos Wool Tranquility Mattress
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Mattress details
Mattress
Hypnos Wool Tranquility Mattress
Size
Firmness
Medium Firm
Construction
Wool
Depth (cm)
29
Layers
5
Layer Details
Viscose Blend Breathable Sleep Surface
A soft viscose blend cover that promotes airflow, which means the sleep surface stays cooler and fresher through the night.
Sustainably Sourced British Wool
British wool gives gentle cushioning with impressive resilience. In practice that means a comfort layer that keeps its shape rather than developing body impressions quickly.
Sustainably Sourced Cotton
Natural cotton fibres are highly breathable and wick away excess moisture. You'll feel this as a cooler, drier surface, particularly useful if you tend to overheat.
eOlus™ Fibres
These fibres offer a soft, foam-like feel while letting air and moisture pass through easily. You get the comfort of foam without the heat retention it's often criticised for.
ReActive™ 8-Turn Pocket Springs
The base is 1400 individually responsive pocket springs, each with 8 turns, engineered for total spinal and body support. Each spring senses and adjusts independently, so movement on one side of the bed is less likely to disturb the other.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Real space for two: With 75cm each for two people sharing, you can both change position freely without meeting in the middle.
- Springs plus width cut disturbance: Pocket springs respond independently, so combined with the wider UK king footprint an early riser can slip out with less chance of waking a partner.
- Length for taller sleepers: At 200cm the UK king is 10cm longer than the UK double, which stops feet hanging over the end for anyone approaching six foot.
- Wool stays comfortable across a shared bed: Two bodies generate more heat than one, and the wool and cotton layers wick moisture so the wider surface stays cooler and drier overnight.
- Fits most master bedrooms: Allow at least 2.7m x 2.9m and this size sits comfortably in a typical UK master with room to walk round both sides.
This size suits you if...
You share the bed every night and a UK double has started to feel cramped, one of you is approaching six foot and wants that extra 10cm of length, or you keep different hours and want enough width that the first person up can leave without a fuss. It also suits couples where a dog has quietly become a regular third occupant.
Consider another size if...
Your bedroom is under our suggested 2.7m x 2.9m minimum, or you sleep alone. In either case we'd recommend the UK double instead, which needs at least 2.6m x 2.8m and still offers generous solo space.
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FAQ's
Is a UK king Hypnos Wool Tranquility big enough for a couple?
Yes, comfortably for most. The UK king measures 150 x 200cm, giving 75cm each for two people sharing, and the 1400 pocket springs move independently so one person shifting is less likely to disturb the other. If one of you sprawls, or a dog joins you most nights, the UK super king adds another 30cm of width.
What room size do I need for the Hypnos Wool Tranquility in a UK king?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. That allowance is our own guidance, and it gives you space for bedside tables and a clear walkway on both sides. New build masters can be tighter than they look once wardrobes go in, so measure the usable floor, not the room on the plan.
Is the UK king long enough for someone over six foot?
At 200cm, or 6ft 6in, it gives most tall sleepers clear headroom. The UK king is 10cm longer than the UK double, and that difference is often what taller sleepers are really upgrading for rather than the width. If you're well past six foot, the UK super king is the same length, so sizing up buys width only.
Should I choose the UK king or UK super king in this mattress?
The UK king is 30cm narrower than the UK super king, and both are the same length. The UK king suits most couples and most rooms; we'd only push you towards the UK super king if your room is at least 3m x 2.9m and you want maximum personal space, perhaps because a pet or child regularly ends up in the bed.
Where can I buy the Hypnos Wool Tranquility in a UK king?
Compare the retailers listed on this page. The prices shown here are live and updated as retailers change them, so they're a better guide than any figure we could print. Whichever retailer you choose, check their own listing for current delivery arrangements before you order, as those details can change.