Millbrook Duke Natural Silk King Size Mattress
The Millbrook Duke Natural Silk is a medium-feel pocket sprung mattress, handmade in England by an NBF-approved manufacturer, with a comfort build of natural silk, sustainably sourced Hampshire wool and fine English cotton.
- Silk & wool reduce heat build-up
- 7-zone support keeps your spine level
- Handmade in England
£699
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Millbrook Duke Natural Silk Mattress
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Mattress details
Mattress
Millbrook Duke Natural Silk Mattress
Size
Firmness
Medium
Construction
Pocket Spring
Wool
Eco-Friendly
Depth (cm)
28
Layers
5
Layer Details
Sleep Surface
A Belgian damask viscose cover that feels silky rather than scratchy against bedding. It's highly breathable, which means moisture escapes rather than lingering, helping the bed feel fresher night after night.
Natural Silk Layer
Silk is lightweight and exceptionally soft, which means a gentle, cushioned first impression when you lie down. It's a genuine luxury filling rather than a marketing flourish.
Sustainably Sourced Hampshire Wool
Wool is naturally elastic and durable, which means the cushioning recovers its shape rather than flattening quickly. It also regulates temperature well, a quiet advantage if you run warm.
Fine English Cotton
Premium English-spun cotton, crafted in the North West of England, adds a soft, breathable comfort layer. Cotton wicks moisture, which means a drier, more comfortable sleeping surface.
Support System
A 7-zone ergonomic pocket spring system with up to 1000 individually responsive springs in a king size, designed to mirror the body's natural contours. Softer cushioning at the shoulders and firmer support through the hips means better spinal alignment, particularly for side sleepers.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Up to 1000 springs at this size: The UK king carries up to 1000 individually responsive pocket springs, which means movement on one side is far less likely to travel to the other.
- 7.5cm more space each than a double: The UK king is 15cm wider than the UK double, giving each sharer 7.5cm more width, a difference you notice every time you roll over.
- Extra length for taller sleepers: At 200cm, it's 10cm longer than a UK double, so a partner over six foot no longer sleeps with feet at the edge.
- Different schedules, less disturbance: Independent springs plus the wider footprint mean an early alarm and a quiet exit on one side barely registers on the other.
- Natural fillings across a bigger surface: Silk, Hampshire wool and English cotton breathe well, so even sharing a larger bed with a warm partner, heat has somewhere to go.
This size suits you if...
You share the bed every night and a double has started to feel cramped, you and your partner keep different hours and want movement on one side to stay on one side, or someone in the bed is nearing six foot and needs the 200cm length as much as the width.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king. In that case we'd recommend the UK double instead, which needs at least 2.6m x 2.8m and still gives two sharers 67.5cm each.
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FAQ's
Is the Millbrook Duke Natural Silk UK king big enough for a couple?
Yes, comfortably for most. At 150cm wide it gives 75cm each, which is 7.5cm more per person than a UK double. Combined with the pocket springs moving independently under each of you, it suits couples where one partner is restless or keeps different hours. Very tall or broad couples might still prefer the UK super king.
How much bigger is the UK king than the double in this mattress?
The UK king is 15cm wider and 10cm longer than the UK double, at 150 x 200cm against 135 x 190cm. The extra width works out at 7.5cm more per person for two sharing, and the extra length matters if either of you is approaching six foot.
What room size do I need for the Millbrook Duke in a UK king?
We suggest at least 2.7m x 2.9m, which leaves enough space to walk round the bed and open drawers. That's our guidance rather than Millbrook's. A new build master bedroom can be tighter than it first appears once wardrobes go in, so measure with furniture in place before deciding.
How many springs does the UK king version have?
Up to 1000 individually responsive pocket springs at this size, arranged in seven zones with softer cushioning at the shoulders and firmer support through the hips. Because each spring moves on its own, a partner getting up hours before you is less likely to wake you across a 150cm-wide bed.
Is a UK king long enough for someone over six foot?
Usually, yes. At 200cm, or 5ft x 6ft 6in overall, the UK king gives a 6ft sleeper around six inches of clearance, where a 190cm double leaves very little. If length is your reason for upgrading, note that the UK super king is the same 200cm long, so sizing up further only adds width.