Arthur Sleep Copper Arthur King Size Mattress
The Copper Arthur from Arthur Sleep is a medium firm pocket spring mattress with a copper-infused fabric cover.
- Copper-infused cover
- Suits back & combination sleepers
- Supportive pocket spring core
£655
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Arthur Sleep Copper Arthur Mattress
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Mattress details
Mattress
Arthur Sleep Copper Arthur Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Depth (cm)
Layers
2
Layer Details
Comfort layer
A 40mm layer of memory foam. It adds a little cushioning over the springs, so the surface feels less bare than springs alone.
Support system
800 pocket springs, each working on its own. That gives the mattress its medium-firm support, and means the springs respond separately as you move or as a partner shifts.
Layer details from mattressman.co.uk and arthursleep.co.uk product pages, October 2026.
Key benefits
- Space to sleep apart, together: With 75cm each for two people sharing, you can both change position without meeting in the middle.
- Pocket springs and width work together: Independent springs already limit motion transfer, which means an early alarm on one side is even less likely to wake the other across a 150cm width.
- Extra length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, so anyone approaching 6ft gets their feet on the mattress rather than off the end.
- Room for a bed-sharing pet: If a dog claims the foot of your bed most nights, the added width means it takes a share rather than the lion's share.
- Medium firm across a wider surface: The medium firm feel supports back and combination sleepers, and the king width lets each of you settle into your own spot without rolling together.
This size suits you if...
You share the bed every night and a UK double has started to feel like a compromise, particularly if one of you gets up hours before the other. It also suits couples where one partner is over six foot, since the 200cm length is a genuine upgrade over the 190cm of a UK double. Allow at least 2.7m x 2.9m of bedroom space.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case we'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is the Copper Arthur in a UK king big enough for a couple?
Yes, comfortably for most. At 150cm wide it gives 75cm each for two people sharing, and the pocket spring construction means the springs move independently, so a restless partner is less disruptive. Couples who want still more space could consider the UK super king, which is 30cm wider than the UK king.
What room size do I need for the Copper Arthur UK king?
We suggest a bedroom of at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. That allowance covers walking space on both sides and drawers that open fully. In a new build master bedroom, measure after accounting for wardrobes, as fitted storage often takes more floor than you expect.
Is the UK king Copper Arthur long enough for tall sleepers?
At 200cm, it's 10cm longer than the UK double, which matters if either of you is approaching or over six foot. Heels hanging off the end of a 190cm mattress is a nightly irritation the extra length removes. If height is your reason for upgrading, the UK king delivers it without demanding a huge room.
Will I feel my partner getting up in a king size Copper Arthur?
Less than in most beds. The pocket springs compress independently, so movement on one side doesn't travel far, and the 150cm width adds physical distance on top. If one of you leaves for work hours before the other, this size and construction together give the later riser a decent chance of sleeping through it.
Should I choose the Copper Arthur in a UK king or a UK super king?
The UK super king is 30cm wider than the UK king, and both are the same length, so the choice is purely about width and room size. We suggest at least 3m x 2.9m for the UK super king. If your room can't spare that, the UK king remains a generous size for two.