Luna 4000 Plush Gel Memory Pocket Hybrid Mattress
The Luna 4000 Plush Gel Memory Pocket Hybrid is a 25cm deep hybrid mattress that pairs a full pocket spring system with gel-infused memory foam, which means you get the contouring hug of foam without losing the responsive support of springs.
- Softer feel for side sleepers
- Mini springs fine-tune pressure relief
- Open-cell foam lets heat escape
£304
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The brand describes the Luna 4000 Plush as soft to medium, so it leans gentler than the average hybrid. It comes in five UK sizes, single up to super king, at a price that's good value for a 4000-spring build. If you sleep warm, the open cell memory foam and breathable knitted cover are designed to run cooler than standard foam, although no foam hybrid sleeps as cool as pure springs.
Mattress specifications
Firmness
Medium Soft
Type
Hybrid
Depth (cm)
25
Number of Layers
5
Trial Period (nights)
100
Warranty (years)
10
Price Range
£304 to £759
Best Sleeping Position(s)
Side Sleeping
Certifications
Assessed from the specification published by Mattress Online, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
Choose this if you want a softer-feeling hybrid at a sensible price. The 4000 springs are split into two layers: full-size Luna pocket springs for core support and mini pocket springs above them for finer pressure relief, which means less of that bouncy, disconnected feel cheaper spring mattresses can have. Side sleepers and lighter bodies tend to get on well with a soft to medium feel, as it lets shoulders and hips sink in rather than pressing back. Mattress Online offers a 100-night trial (a mattress protector purchase from them is required for eligibility) and a 10-year guarantee, which gives you a decent safety net for the money.
Key features & layer details
Knitted cover
A soft knitted top designed to enhance airflow and breathability. It adds a cosy, slightly plush first impression when you lie down.
Luna Fusion Cool Memory Foam
A 2cm layer of open cell memory foam, which means it lets heat escape more readily than standard memory foam while still moulding to your shape. It provides that gentle, cradled feel memory foam is known for.
Reflex Foam
Two 3cm layers of supportive foam that mould to your body and help keep your spine aligned. This is the transition zone between the soft top and the springs below.
Mini Pocket Springs
Small, individually cased springs that add a layer of fine-tuned pressure relief and reduce motion transfer, which means less disturbance when a partner shifts in the night.
Luna Pocket Springs
Full-size steel springs sewn into individual fabric pockets, each responding independently to your weight and movement. This is the mattress's main support system, keeping your body properly aligned.
Layer details from mattressonline.co.uk product page, September 2026.
Best suited for?
Side sleepers
A soft to medium feel lets shoulders and hips sink in rather than pressing back, which suits the way side sleeping loads the body.
Lighter sleepers
The plush knitted cover and gentle memory foam layer give lighter bodies enough sink to feel cradled without needing a heavy frame to compress the comfort layers.
Couples
Mini pocket springs reduce motion transfer, which means you are less likely to be disturbed when a partner shifts in the night.
Warm sleepers
Open cell memory foam and a breathable knitted cover let heat escape more readily than standard foam, though pure springs still sleep cooler.
Budget buyers
Good value for a 4000-spring build, with a 10-year guarantee and a 100-night trial adding a decent safety net for the money.
If you prefer a firm mattress, or you're a heavier back or stomach sleeper who needs a more solid surface to stay aligned, this soft to medium feel may let you sink too far. Owner feedback also mentions the lack of side handles, so if you rotate your mattress often, that's a slight nuisance.
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.
Luna 4000 Plush Gel Memory Pocket Hybrid Mattress
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FAQ's
Is the Luna 4000 soft or firm?
It's rated soft to medium, so it sits on the gentler end of the scale. That suits side sleepers and lighter bodies well, although heavier sleepers or committed stomach sleepers may want something firmer.
How many springs does the Luna 4000 mattress have?
4000 in total: 2000 full-size Luna pocket springs for core support, topped with 2000 mini pocket springs that add pressure relief and reduce motion transfer between partners.
Does the Luna 4000 mattress come with a trial?
Mattress Online offers a 100-night trial, but only if you also buy a mattress protector from them. That condition matters, so check it before ordering if the trial is a deciding factor for you.
How deep is the Luna 4000 Plush mattress?
It's 25cm deep, a fairly standard depth for a hybrid. Most fitted sheets designed for standard or deep mattresses should fit without any trouble.
Does the Luna 4000 have a guarantee?
Yes, the retailer listing states a 10-year guarantee. As with any guarantee, it covers manufacturing faults rather than gradual softening from normal use, so keep your proof of purchase.
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