Arthur Sleep Royal Arthur King Size Mattress
The Royal Arthur from Arthur Sleep is a pocket spring mattress with 3,000 springs, which means each spring moves independently, so you get support that follows your shape rather than a rigid, uniform surface.
- Support adjusts to hips & shoulders
- Firm feel for back & front sleepers
- Minimises partner disturbance
£859.50
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Arthur Sleep Royal Arthur Mattress
More available sizes
Mattress details
Mattress
Arthur Sleep Royal Arthur Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Depth (cm)
Layers
2
Layer Details
Gel foam comfort layer
A layer of gel foam sits at the top as the comfort and filling layer. Gel foam is associated with cooling comfort, which suits you if you tend to feel the heat at night.
3000 pocket springs
The support system is made up of 3,000 pocket springs, each working on its own. That lets the mattress respond to your body shape, and it gives the firm, supportive feel the Royal Arthur is built around.
Layer details from mattressman.co.uk and arthursleep.co.uk product pages, October 2026.
Key benefits
- Room to sleep apart, together: The UK king is 15cm wider than the UK double, which means you both get space to shift position without landing on each other.
- 3,000 springs across a wider bed: With 75cm each and springs that move independently, one partner turning over is far less likely to wake the other.
- Extra length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, a real difference if one of you is approaching six foot.
- Firm support at couple width: The firm tension keeps back and front sleepers level across the full 150cm, rather than rolling towards the middle.
- Fits a normal master bedroom: We suggest at least 2.7m x 2.9m, which most UK master bedrooms can manage with bedside tables on both sides.
This size suits you if...
You share the bed every night and a double now feels tight, especially if one of you turns often or gets up hours before the other. The independent springs and extra width mean an early alarm on one side is less likely to disturb the other. It also suits couples where one partner is tall, since the 10cm of extra length over a UK double matters more than you'd expect.
Consider another size if...
Your bedroom is under our suggested 2.7m x 2.9m minimum, or you sleep alone. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m and still offers the same firm 3,000-spring feel.
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FAQ's
Is a UK king big enough for a couple on the Royal Arthur?
Comfortably, for most. At 150 x 200cm you get 75cm each for two people sharing, and the 3,000 pocket springs respond to each of you separately, so movement on one side carries less to the other. If you both sprawl, or a dog claims a share of the bed most nights, the UK super king is the roomier option.
Will the king size Royal Arthur suit a tall sleeper?
This is one of the better reasons to pick it. The UK king is 200cm long, 10cm longer than the UK double, which stops anyone approaching six foot sleeping with their feet at the very edge. The firm tension also suits back and front sleepers, who tend to feel short mattresses most.
What room size do I need for the Royal Arthur in a UK king?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. Measure with wardrobes and drawers in place, since a new build master bedroom can shrink quickly once furniture goes in. If your room falls short, the UK double needs at least 2.6m x 2.8m and may be the wiser buy.
Should I get the Royal Arthur in a king or a super king?
The UK king is 30cm narrower than the UK super king; both are the same 200cm length. Sizing up helps if you're propping pillows through pregnancy, recovering from surgery, or simply want maximum space, but you'll need a room of at least 3m x 2.9m. For most couples the UK king is the sensible middle ground.
Does one partner getting up early disturb the other on this mattress?
Less than on a smaller or plainer bed. The 3,000 pocket springs move independently, so climbing out on one side transfers little motion across, and the 150cm width means you're rarely pressed together to begin with. No mattress removes disturbance entirely, but this combination is well suited to mismatched schedules.