Millbrook Baroness Natural Wool Double Mattress
The Millbrook Baroness Natural Wool Mattress is a medium firm natural mattress built around sustainably sourced Hampshire wool, fine English cotton and 7-zone pocket springs, which means cushioned comfort with slightly firmer support where your hips and back need it.
- Natural wool helps regulate temperature
- 7-zone support, softer at shoulders
- Suits side & back sleepers
£499
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Millbrook Baroness Natural Wool Mattress
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Mattress details
Mattress
Millbrook Baroness Natural Wool Mattress
Size
Firmness
Medium Firm
Construction
Wool
Natural
Depth (cm)
25
Layers
4
Layer Details
Sleep Surface
A Belgian damask viscose cover that feels silky and soft to the touch. It's highly breathable, which means a fresher sleeping environment through the night.
Comfort Fillings
Sustainably sourced Hampshire wool sits beneath the cover, giving a cosy, cushioning feel. Wool is known for its durability and elasticity, so this layer should keep its shape well.
Comfort Fillings
A layer of fine English cotton, spun and crafted in the North West of England. Cotton adds softness and helps the mattress breathe.
Support System
7-zone ergonomic pocket springs, up to 1000 individually responsive springs in a king size, with the count varying by size. The zoning gives softer comfort at the shoulders and firmer support at the hips and back, which means better spinal alignment for most sleepers.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- A shared size for typical rooms: At 135cm wide, the UK double fits bedrooms where a UK king would leave you squeezing past the footboard every morning.
- 67.5cm each for two sharing: Two people get 67.5cm of width apiece, enough for most couples, and the zoned springs support each sleeper's hips independently.
- Breathable wool at close quarters: Sharing a bed raises the temperature under the duvet, and the naturally breathable Hampshire wool helps the surface stay fresher than synthetic foams tend to.
- Room for bedside tables both sides: In a room around the 2.6m x 2.8m minimum, a UK double usually still allows a bedside table on each side, which a wider size often rules out.
- Easy to dress: Double sheets and a 200 x 200cm double duvet are stocked everywhere at every price, handy if you're furnishing a whole home at once.
This size suits you if...
You share the bed every night and your bedroom is a typical UK size, comfortably clearing our suggested 2.6m x 2.8m minimum but without space to spare for anything wider. Or you sleep alone and want proper room to spread out, perhaps with a dog or cat claiming a corner. It also makes sense for a guest room that regularly hosts visiting couples.
Consider another size if...
You're a couple with a bedroom of at least 2.7m x 2.9m and either of you feels cramped on 67.5cm of width. We'd recommend the UK king instead: it gives 75cm each for two sharing, so 7.5cm more per person, plus 10cm of extra length.
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FAQ's
Is the Millbrook Baroness in a UK double big enough for a couple?
For most couples, yes. Two people sharing a UK double get 67.5cm of width each, and the 7-zone pocket springs respond to each sleeper individually, so one person's weight doesn't pull the other out of alignment. If either of you is broad shouldered or a restless sleeper, the UK king gives 75cm each instead.
What room size do I need for the Baroness UK double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That allows walking space on both sides and, in most layouts, a bedside table each. Our figures are guidance rather than a rule: measure your own room with wardrobes and drawers marked out before you decide.
Should I get the Baroness in a UK double or a UK king?
It usually comes down to your room. The UK double is 15cm narrower and 10cm shorter than the UK king, and we suggest at least 2.7m x 2.9m for the UK king against 2.6m x 2.8m for the UK double. If the bigger room guidance fits your bedroom comfortably, couples generally appreciate the extra 7.5cm each.
How big is the Millbrook Baroness double in feet?
The UK double measures 4ft 6in x 6ft 3in, which is 135 x 190cm. It's the same length as the UK single and the UK small double, just wider, so if you're replacing either of those the bed won't sit any further into the room, it will only spread sideways.
Will a double mattress fit up the stairs in an older house?
A 135cm wide mattress will turn most staircases, although tight winders in older terraces and narrow new build landings can be awkward. Pocket sprung mattresses like the Baroness flex less than all-foam designs, so measure the tightest turn before ordering, and check the delivery terms with the retailer listed on this page.