Coolflex Hybrid CHILL Mattress
The Coolflex Hybrid CHILL is a medium-feel hybrid built around cooling, with a gel-infused memory foam layer designed to draw heat away from you and a stitched-in pillow top for softness on top of the springs.
- Cool gel foam regulates temperature
- Plush pillow top that springs back
- Helps keep your spine aligned
£399
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At 37cm deep with 2000 springs in total, the Coolflex Hybrid CHILL is a substantial mattress for its price. It carries a Which? Best Buy award for double mattresses (January 2026), which gives some independent reassurance, and it's hypoallergenic and vegan friendly. If you sleep hot and want a forgiving, cushioned feel without spending a fortune, it's a sensible shortlist candidate.
Mattress specifications
Firmness
Medium
Type
Hybrid
Depth (cm)
37
Number of Layers
4
Trial Period (nights)
Warranty (years)
5
Price Range
£399 to £599
Best Sleeping Position(s)
Side Sleeping
Back Sleeping
Combination Sleeping
Certifications
BS 7177
Assessed from Coolflex's published specification for this mattress, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
Cooling is the main draw here. The Cool Gel Memory Foam is infused with gel microbeads to regulate temperature, which means less of that clammy, sinking-in warmth traditional memory foam can create. The pillow top contains up to 1200 mini pocket springs, so the surface feels plush but still springs back rather than leaving body impressions. Underneath, up to 800 individually pocketed springs move independently, which means support goes where your body needs it and your spine stays aligned. The medium firmness suits most sleeping positions, and the starting price is good value for a 37cm hybrid. A 5-year guarantee and free next day delivery round it off.
Key features & layer details
Pillow Top
A plush pillow top with up to 1200 mini pocket springs, working like a stitched-in mattress topper. You get that soft, cushioned first touch without needing to buy a separate topper.
Cool Gel Memory Foam
Memory foam infused with gel microbeads to regulate temperature and improve breathability, designed to draw heat away from the body. In practice, that means the contouring feel of memory foam with less heat build-up overnight.
Comfort Foam
Layers of Comfort Foam that cradle pressure points and relieve pressure across the whole body. Side sleepers should notice this most around the hips and shoulders.
Pocket Springs
Up to 800 individually pocketed springs that move independently to target support where you need it and keep your spine aligned. Independent movement also means less disturbance when a partner shifts position.
Layer details from mattressnextday.co.uk product page, September 2026.
Best suited for?
Warm sleepers
Gel microbeads in the Cool Gel Memory Foam regulate temperature and draw heat away, so you get contouring comfort with less overnight heat build-up.
Side sleepers
Comfort Foam layers cradle pressure points, and you should notice this most around the hips and shoulders where side sleeping puts the most weight.
Couples
Up to 800 individually pocketed springs move independently, which means you are less likely to feel your partner shifting position during the night.
Combination sleepers
Medium firmness suits most sleeping positions, and the mini pocket springs in the pillow top spring back instead of leaving body impressions as you turn.
Allergy sufferers
The copy describes this mattress as hypoallergenic, which makes it a sensible choice if you want bedding that is less likely to irritate.
If you prefer a firm, supportive surface, the plush pillow top will likely feel too soft. Heavier sleepers who need pronounced pushback may sink further than they'd like into the comfort layers. And at 37cm deep, it's a tall mattress: standard fitted sheets may struggle, so check yours first.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Coolflex Hybrid CHILL Mattress
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FAQ's
Is the Coolflex Hybrid CHILL mattress good for hot sleepers?
Yes, cooling is its main selling point. The gel-infused memory foam is designed to draw heat away from the body, and owner reviews specifically praise its cooling properties. If overheating is your biggest complaint at night, this is one of the more sensible picks at a mid-range starting price.
How firm is the Coolflex Hybrid CHILL?
It's a medium. Combined with the plush pillow top, that gives a cushioned, forgiving feel that suits all sleeping positions according to owner feedback, although if you prefer a properly firm mattress, this might not be the best choice.
How many springs does the Coolflex Hybrid CHILL have?
2000 in total: up to 1200 mini pocket springs in the pillow top and up to 800 full-size pocket springs in the support base. Because they're individually pocketed, each spring moves independently, which helps with pressure relief and reduces partner disturbance.
What guarantee does the Coolflex Hybrid CHILL come with?
It comes with a 5-year guarantee, along with free next day delivery. Some brands offer longer cover, but five years is reasonable at a mid-range starting price.
What sizes is the Coolflex Hybrid CHILL available in?
Five UK sizes: Single, Small Double, Double, King and Super King. Bear in mind it's 37cm deep, so you may need deep or extra-deep fitted sheets.
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