Arthur Sleep King Arthur Double Mattress
The King Arthur from Arthur Sleep is a pocket spring mattress in a medium firm tension, which means springs that respond to your body individually rather than as one block, with a supportive rather than sink-in feel.
- Medium-firm for side & back sleepers
- Minimises partner disturbance
- Support follows your body's shape
£565
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Arthur Sleep King Arthur Mattress
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Mattress details
Mattress
Arthur Sleep King Arthur Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Depth (cm)
Layers
3
Layer Details
Memory foam comfort layer
A 20mm layer of memory foam sits in the comfort layer, as specified by the brand. It adds a little cushioning over the springs beneath, so the surface has some give without feeling like a deep foam hug.
Mini pocket springs
An additional layer of 1200 mini springs sits within the top of the mattress. Smaller springs can respond more closely to your body's shape, so they add finer contouring over the main spring unit below.
Base pocket springs
800 pocket springs form the base of the mattress. Each spring moves independently, which gives the underlying support and helps limit how much you feel a partner moving.
Layer details from mattressman.co.uk and arthursleep.co.uk product pages, October 2026.
Key benefits
- Two people, sensible footprint: At 135 x 190cm you get 67.5cm each for two people sharing, in a size that fits rooms where a UK king would feel cramped.
- Room for bedside tables: In an average-sized bedroom a UK double usually leaves space for tables on both sides of the bed, which a wider size often steals.
- Pocket springs help sharers: Each spring moves independently, which means a partner turning over disturbs you less, and that matters most at this shared width.
- Easy bedding: Double sheets and duvets are sold everywhere at every price, so dressing this size costs less effort and money than the less common sizes.
- A safe guest room choice: If this is for a spare room, a UK double comfortably sleeps visiting couples without demanding a large room to house it.
This size suits you if...
You share the bed every night and your bedroom is a typical UK size, around our suggested minimum of 2.6m x 2.8m or a little larger. It also suits you if you're furnishing a guest room that needs to sleep visiting couples, or you sleep alone and want space to spread out without moving to a bigger room.
Consider another size if...
You and your partner both like space and your room measures at least 2.7m x 2.9m. In that case we'd recommend the UK king instead: it's 15cm wider and 10cm longer than the UK double.
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FAQ's
Is the UK double King Arthur mattress big enough for a couple?
Yes, for most couples. The UK double gives 67.5cm each for two people sharing, and the pocket springs respond to each of you individually, so movement transfers less across that shared width. If either of you is tall or a restless sleeper, the UK king adds 15cm of width and 10cm of length.
What room size do I need for the King Arthur in a UK double?
We suggest at least 2.6m x 2.8m, which is our own guidance rather than the brand's. That allows walking space around the bed, and in most rooms of that size you'll still fit bedside tables on both sides. Around 3m x 3m is the comfortable norm.
Should I buy the King Arthur in a UK double or a UK king?
It 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. If your bedroom clears that with room to spare, the extra width is a genuine comfort gain for couples; if not, the UK double is the sensible pick.
How big is the King Arthur mattress in a UK double?
It measures 135 x 190cm, which is 4ft 6in x 6ft 3in. That's the long standing UK standard for two people sharing. Arthur Sleep doesn't publish the depth of this mattress, so check the retailer listing if your fitted sheets have a snug fit.
Is the UK double a good choice for a guest room?
It's the safest guest room size. Visiting couples can share it comfortably, solo guests get room to spread out, and the medium firm tension is a middle ground most people tolerate well for short stays. It also fits smaller spare rooms where a UK king would leave little walking space.