Millbrook Duke Natural Silk Super King 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
£799
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Millbrook Duke Natural Silk Mattress
More available sizes
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
- Distance beats any spring count: The pocket springs move independently to absorb a partner's movement, but 90cm each for two people sharing means much of that movement never reaches you at all.
- Space when children appear at 3am: At 180cm wide there's genuine room for a small visitor between you without anyone being pressed to the edge, something a UK king manages far less gracefully.
- Natural fillings across a bigger surface: Silk, Hampshire wool and English cotton breathe well, which means less trapped heat even with three bodies, or a dog, sharing the bed.
- 15cm more each than a UK king: The UK king gives 75cm each for two sharing, so the UK super king gives 15cm more each, roughly an extra shoulder's width per person.
- A bed that fills a large room: In a big master bedroom a smaller bed can look undersized; at 6ft x 6ft 6in this one holds its own without crowding the space.
This size suits you if...
You share the bed every night and want the maximum sleeping space standard UK retailers stock, your partner is genuinely restless and you'd rather sleep out of reach, or children and pets treat your bed as theirs too. Your bedroom should comfortably clear 3m x 2.9m, and ideally more, so the mattress doesn't dominate the room.
Consider another size if...
Your bedroom falls short of the 3m x 2.9m we suggest as a minimum, or you sleep alone. The UK king would suit you better: it's the same length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
How much space does each person get on a super king Millbrook Duke Natural Silk?
Two people sharing get 90cm each, the same width as a UK single apiece. Combined with the pocket springs, which compress independently under each sleeper, that distance makes a restless partner much easier to sleep through. It's the main reason couples size up from a UK king, which gives 75cm each.
Is the Millbrook Duke Natural Silk super king big enough for co-sleeping with children?
It's the most practical size for it. At 180cm wide, a child wandering in at night can settle between you and everyone still has a reasonable share. The natural silk, wool and cotton fillings breathe well, which helps when extra bodies raise the temperature under the duvet. A large dog is manageable for the same reason.
What room size do I need for the Millbrook Duke Natural Silk in a UK super king?
We suggest at least 3m x 2.9m, with around 3.5m x 3.2m feeling more comfortable, allowing walking space and bedside tables on both sides. Measure door swing and any tight landing turns too: at 180 x 200cm this is a large item to move, so check the route upstairs before ordering.
Should I get the super king or the UK king Millbrook Duke Natural Silk?
If your room clears 3m x 2.9m and you share the bed, the UK super king is 30cm wider than the UK king, giving 15cm more each. Both are the same length, so you gain nothing there. In a smaller room the UK king is the sensible pick; we suggest at least 2.7m x 2.9m for it.
Where can I buy the Millbrook Duke Natural Silk in a super king?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them. Because this is a handmade natural-fibre mattress, stock in the largest size can move around, so it's worth checking back if your preferred retailer shows nothing today.