Firmness
Medium Firm
Type
Pocket Spring
Depth (cm)
29
Number of Layers
3
Trial Period (nights)
100
Warranty (years)
5
Price Range
£599 to £1,049
Best Sleeping Position(s)
Certifications
Assessed from the specification published by Mattress Online, captured September 2026, and from regular price comparison across our UK retail partners.
The main draw here is the wool. It's naturally temperature-regulating, which means it helps in both summer and winter rather than trapping heat the way some synthetic-heavy mattresses can. Beneath it, 3000 pocket springs made from twice tempered steel adapt individually to your body shape, so you and a partner get support tailored to each of you rather than a shared, wobbly middle. At 29cm deep it has a substantial, traditional feel. Buying through Mattress Online adds a 100-night trial and free next day weekday delivery, with old mattress removal available for £35. The guarantee is 5 years, shorter than some brands offer, but the from-price of £599 keeps it reasonable for a wool pocket sprung mattress.
Key Features & what's inside
- Soft White Fibres. Soft synthetic fillings topped with a polyester layer, which means a cosy surface feel the moment you lie down. They're inherently breathable, so this comfort layer shouldn't hold onto heat.
- Wool. A generous layer of natural wool fibres gives deep, plush comfort. Wool is naturally temperature-regulating, which means it works all year round, warming in winter and wicking heat in summer.
- Pocket Springs. 3000 traditional pocket springs made from twice tempered steel, which means each spring responds to your body shape independently rather than the whole surface moving as one. The result is strong, personalised support and less partner disturbance.
Layer details from mattressonline.co.uk product page, September 2026.
Who's it NOT for?
If you sleep hot and prefer a shallow, springy modern hybrid, the deep fibre and wool fillings may feel too plush and traditional. Lightweight side sleepers wanting a genuinely soft surface should also be cautious: it's listed as Medium, but at least one owner found it firm at first.
Wentworth Mercer Deluxe Wool 3000 Pocket Mattress
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How firm is the Wentworth Mercer Deluxe Wool 3000?
The product page lists it as Medium. That said, one customer described it as firm rather than medium when new, noting it softened with use and a topper. If you're a lighter sleeper or firmly prefer a soft feel, treat it as sitting toward the firmer side of medium.
Does the Wentworth Mercer Deluxe Wool 3000 come with a trial?
Mattress Online lists a 100-night trial with this mattress. That trial is the retailer's own offer rather than a manufacturer promise, so if you buy elsewhere, check that seller's returns terms before ordering.
How long is the guarantee on this mattress?
It comes with a 5 year guarantee, as listed by the retailer. That's shorter than some brands offer, but reasonable at this price point.
Is the Wentworth Mercer Deluxe Wool 3000 good for hot sleepers?
It should cope well with moderate overheating. The wool layer is naturally temperature-regulating and the soft white fibre layer is breathable, so heat has routes to escape. There's no foam to trap warmth, which helps.
What sizes does the Wentworth Mercer Deluxe Wool 3000 come in?
Five UK sizes: Single, Small Double, Double, King and Super King. Prices range from £599 to £1,049 depending on the size you choose.
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