Firmness
Type
Pocket Spring
Depth (cm)
29
Number of Layers
5
Trial Period (nights)
Warranty (years)
5
Price Range
£679 to £1,399
Best Sleeping Position(s)
Certifications
Assessed from the specification published by MattressNextDay, captured September 2026, and from regular price comparison across our UK retail partners.
The appeal here is temperature and support. Wool and cotton naturally wick moisture, which means you're less likely to wake up clammy than on an all-foam mattress, and the eOlus fibre layer adds a soft, foam-like feel while still letting air pass through. Beneath that, 1400 pocket springs with 8 turns each respond independently to your body, so a heavier hip can sink while a lighter shoulder stays supported. The medium firm feel suits most back and combination sleepers. It's hypoallergenic and meets the BS7177 fire safety standard. At mattressnextday.co.uk, currently the only listed retailer, delivery is free and next day, flat rather than rolled.
Key Features & what's inside
- 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.
Who's it NOT for?
If you like a soft, sink-in feel, the medium firm tension here will likely feel too solid, and lightweight side sleepers may find it a little firm at the shoulder. Anyone who wants to try before committing should also pause: no trial period is listed by the retailer or by Hypnos.
Hypnos Wool Tranquility Mattress
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How firm is the Hypnos Wool Tranquility mattress?
It's rated medium firm. That tension suits most back and combination sleepers, although lightweight side sleepers may find it slightly too firm for comfortable pressure relief at the shoulders and hips.
Does the Hypnos Wool Tranquility come with a trial period?
No trial period is stated on the retailer listing, and no manufacturer trial is mentioned either. If a sleep trial matters to you, check terms directly with the retailer before ordering.
What guarantee does the Hypnos Wool Tranquility have?
It comes with a 5-year Hypnos manufacturer guarantee, as stated on the mattressnextday.co.uk listing. That's shorter than some brands offer, but it comes from an NBF-approved UK manufacturer with audited build quality.
Is the Hypnos Wool Tranquility good for hot sleepers?
It's a strong option. Wool and cotton layers naturally wick moisture, the viscose blend cover promotes airflow, and the eOlus fibre layer is designed not to retain heat or sweat, so it should sleep noticeably cooler than most foam-heavy mattresses.
How is the Hypnos Wool Tranquility delivered?
Mattressnextday.co.uk offers free next day delivery, and the mattress arrives flat rather than vacuum-rolled. That's a retailer offer, so terms may differ if it becomes available elsewhere. Flat delivery means no waiting for it to expand, but do check access for larger sizes.
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