Arthur Sleep King Arthur 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
£439
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The King Arthur comes in both UK and EU sizes, from a UK Single up to a Super King. It's sold through Mattressman, which lists free next day delivery and a 60-night trial on this model. Full construction details, such as spring count and depth, aren't published, so if you like to compare specs line by line, that's a gap.
Mattress specifications
Firmness
Medium Firm
Type
Pocket Spring
Depth (cm)
Number of Layers
3
Trial Period (nights)
60
Warranty (years)
Price Range
£439 to £665
Best Sleeping Position(s)
Back Sleeping
Stomach Sleeping
Combination Sleeping
Certifications
Assessed from the specification published by Mattress Man, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
Pocket springs suit most sleepers because each spring moves independently, which means less disturbance from a partner turning over and support that follows the shape of your body. The medium firm tension is a sensible middle ground: enough give for side sleepers of average build, enough resistance for back sleepers. It sits at the affordable end for a pocket sprung mattress, and the size range is broader than many, including EU sizes that can be hard to find. If you buy through Mattressman, their 60-night trial gives you time to judge it at home rather than in a shop for five minutes.
Key features & 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.
Best suited for?
Couples
Pocket springs move independently, which means less disturbance when your partner turns over, and the range runs up to a Super King for more room.
Back sleepers
The medium firm tension gives enough resistance for the body to stay well supported, while the pocket springs follow your shape.
Budget buyers
The copy places it at the affordable end for a pocket sprung mattress, so you get independent springs without paying top-tier money.
European bed frames
Its range includes EU sizes that can be hard to find elsewhere, so it suits frames built to continental dimensions.
If you prefer a soft, cradling feel, medium firm may feel a little unyielding, particularly for lightweight side sleepers. Spec-driven buyers should note that spring count, depth and guarantee details aren't published for this model, so you'll be buying somewhat on trust. If you prefer memory foam, you won't find that slow-sinking hug here.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Arthur Sleep King Arthur Mattress
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FAQ's
How firm is the Arthur Sleep King Arthur mattress?
It's a medium firm tension. In practice that means a supportive surface with some give, generally comfortable for back and combination sleepers. Lighter side sleepers may find it slightly too firm, while heavier sleepers often get on well with this level of support.
How much does the King Arthur mattress cost?
It depends on the size you choose, and the price table on this page shows the current price for each size. It sits at an accessible price for a pocket spring mattress, though bear in mind detailed construction specs aren't published, so you can't verify spring counts before buying.
What sizes does the Arthur Sleep King Arthur come in?
It comes in eight sizes: UK Single, UK Small Double, UK Double, UK King and UK Super King, plus EU Single, EU Double and EU King. The EU options are useful if you have a continental bed frame, which many brands don't cater for.
Does the King Arthur mattress come with a trial?
Mattressman offers a 60-night trial. That's the retailer's own term rather than a manufacturer promise, so if you buy elsewhere, check that seller's returns policy. Sixty nights is enough time for your body to properly adjust to a new mattress.
How quickly is the King Arthur mattress delivered?
Mattressman lists free next day delivery, with a transit time of one to three days. As with the trial, this is the retailer's own offer, so delivery terms may differ if you find the mattress through another seller.
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