Arthur Sleep Royal Arthur Super King 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
£947.75
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Arthur Sleep Royal Arthur Mattress
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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
- 90cm each for two sleepers: Two people sharing get 90cm each, which means a partner who turns all night is far enough away to ignore.
- 3,000 springs across a wider surface: The independent pocket springs respond to each sleeper separately, so movement on one side stays on that side, useful at this width.
- Room for the whole household: When children appear at 3am or the dog treats the bed as home, 180cm of width means nobody ends up clinging to an edge.
- Firm support that holds its shape: The firm tension keeps a flat, solid surface even with three bodies aboard, rather than everyone rolling into a dip in the middle.
- 30cm more than a UK king: That extra width over the UK king is roughly a whole extra shoulder of space per person, at the same 200cm length.
This size suits you if...
You share the bed every night and want the most space any standard UK size offers, your sleep is regularly interrupted by a partner who fidgets, or children and pets join you often enough that a UK king feels crowded. Your bedroom is comfortably large, and you sleep on your back or front, or simply prefer a firm bed.
Consider another size if...
Your bedroom is under our suggested 3m x 2.9m minimum, or the bed is mostly for two undisturbed sleepers. The Royal Arthur in a UK king would suit you better: 30cm narrower, the same 200cm length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
Will the Royal Arthur super king fit in my bedroom?
The mattress itself is 180 x 200cm. We suggest a room of at least 3m x 2.9m so you can walk round it and open drawers, and around 3.5m x 3.2m feels right. In a loft conversion, check the slope too: at this width, which wall the bed takes is usually decided for you.
Is the Royal Arthur super king good for couples with children who climb in?
It's one of the better cases for this size. At 180cm wide there's genuine room for a small visitor between you, and the firm tension keeps the surface level rather than tipping everyone towards the middle. The 3,000 pocket springs also limit how much a wriggling child disturbs the adults either side.
How much bigger is the super king Royal Arthur than the UK king?
The UK super king is 30cm wider than the UK king, and the two are the same length at 200cm. That width is the whole point: with 90cm each for two people sharing, a restless partner becomes much easier to sleep through. If your room can take it, the upgrade is all usable space.
Does a super king actually help with a restless partner?
More than any comfort layer can. Distance is what stops you feeling someone turn over, and 90cm each is close to a single bed's worth of space per person. On the Royal Arthur, the independent pocket springs add to that by keeping movement local, so their side moves and yours largely doesn't.
What should I check before buying the Royal Arthur in a super king?
Measure the route in, since staircases with tight landing turns and narrow door swings catch people out at this width. Budget for super king bedding as well: sheets in this size and a 260 x 220cm duvet cost more than their UK king equivalents. Get those two right and the size itself rarely disappoints.