Hypnos Cawthorne Deluxe King Size Mattress
The Hypnos Cawthorne Deluxe is a 25cm deep pocket spring mattress with 1000 ReActive springs, each held in its own fabric pocket so they move independently and respond to where your body needs support.
- Foam-free pocket spring comfort
- Breathable fibres keep you cooler
- Made with recycled fibres
£699
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Hypnos Cawthorne Deluxe Mattress
More available sizes
Mattress details
Mattress
Hypnos Cawthorne Deluxe Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Eco-Friendly
Depth (cm)
25
Layers
5
Layer Details
Soft White Fibres
Soft synthetic fillings sit at the top to create a cosy feel. They're durable and resilient, which means the surface should hold its shape rather than flattening quickly.
Solotex™ fibres
A plush, highly breathable layer that increases airflow through the mattress. This helps dispel heat and moisture, so the sleep surface feels fresher through the night.
eOlus™ fibre layer
Made from recycled material, this layer adds cushioning with a slightly firmer feel. It's there to keep you supported and comfortable all night.
Dual density polyester fibre pad
One side adds an extra touch of comfort for you, the other supports the spring unit. Together they help distribute your weight evenly across the mattress.
Pocket Springs (ReActive™)
1000 ReActive springs sit in individual fabric pockets and move independently. That means they respond to movement and target the areas of your body that need support.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Space that calms a shared bed: At 75cm each for two people sharing, you can both change position freely, which matters most in the small hours when one of you is restless.
- Springs that keep movement local: The 1000 ReActive pocket springs move independently, so a partner getting up for an early shift disturbs their side of the UK king far more than yours.
- Length for taller sleepers: The UK king runs to 200cm, 10cm longer than the UK double, which means anyone approaching six foot stops sleeping with their feet at the edge.
- Cooler across a bigger surface: The Solotex fibre layer increases airflow, and with more mattress between you, two warm bodies share less heat than they would in a double.
- A manageable footprint: At 5ft x 6ft 6in, the UK king brings real extra room without the floor space a UK super king demands; we suggest a bedroom of at least 2.7m x 2.9m.
This size suits you if...
You share the bed every night and the double has started to feel like a negotiation, you and your partner keep different hours and want movement on one side to stay on that side, or one of you is tall enough that the standard 190cm length has always been slightly too short. The UK king solves all three in one purchase.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case we'd recommend the UK double instead, which needs a smaller room at around 2.6m x 2.8m.
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FAQ's
Is the Hypnos Cawthorne Deluxe in a UK king good for couples?
Yes, and it's arguably the size this mattress makes most sense in for two people. You get 75cm of width each, and the 1000 pocket springs respond independently to each sleeper's weight, so a lighter partner isn't rolled towards a heavier one. Restless sleepers on different schedules will feel the benefit most.
How much bigger is the UK king than the double for this mattress?
The UK king is 15cm wider than the UK double and 10cm longer. The width is what you notice night to night as a couple; the length is the quieter win, giving taller sleepers room to stretch out fully on the fibre-topped surface rather than curling to fit.
What room size do I need for the Cawthorne Deluxe in a UK king?
We suggest a bedroom of at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. That's our guidance rather than Hypnos's, and it assumes you want to walk around the bed and open drawers. New build master bedrooms can shrink quickly once fitted wardrobes go in, so measure the usable floor, at the wall skirting.
Does the UK king help if my partner gets up earlier than me?
It helps twice over. The extra width means they can slide out without climbing past you, and because each of the 1000 springs sits in its own fabric pocket, the movement of someone leaving the bed stays largely on their side. It won't make an early alarm silent, but the mattress itself transfers noticeably less motion.
Where can I find the best price on the Hypnos Cawthorne Deluxe UK king?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so the table reflects what you'd actually pay today rather than a figure that was true last month. Check whether the listing you choose includes the size you want in stock before ordering.