Arthur Sleep Cool Pocket Super King Mattress
The Arthur Sleep Cool Pocket Mattress is a medium firm pocket spring mattress with 800 pocket springs and a gel foam comfort layer, which means you get targeted support with a top layer designed to draw heat away.
- Gel foam layer keeps you cooler
- Medium-firm feel suits most sleepers
- 60-night trial & 10-year guarantee
£309
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Arthur Sleep Cool Pocket Mattress
More available sizes
Mattress details
Mattress
Arthur Sleep Cool Pocket Mattress
Size
Firmness
Medium Firm
Construction
Foam
Pocket Spring
Depth (cm)
25
Layers
2
Layer Details
Gel foam comfort layer
A breathable gel foam layer that draws heat away from your body. In practice, this means a cooler sleeping surface than standard foam.
800 pocket spring support system
800 responsive pocket springs that move independently, giving targeted support where you need it. This also helps limit motion transfer if you share the bed.
Layer details from arthursleep.co.uk product page, September 2026.
Key benefits
- 90cm of width each: Two people sharing get 90cm each, which means a partner who turns over frequently becomes far easier to sleep through.
- Pocket springs at full width: The 800 pocket springs move independently, so movement on one side of a 180cm-wide bed is even less likely to reach you.
- Room for the whole household: When children pad in at 3am or the dog treats the bed as routine, this size means everyone still gets a workable share.
- Cool surface, big footprint: The gel foam comfort layer draws heat away, useful when three or four warm bodies end up under one duvet.
- Fills a larger master properly: In a period property or generous new build master bedroom, a UK king can look undersized against the wall; this size suits the room.
This size suits you if...
You share the bed every night and want the maximum space UK retailers stock as standard, you sleep next to someone genuinely restless and have learned that distance works better than any comfort layer, or your children or pets join you often enough that a smaller bed leaves someone pressed against the edge. Your bedroom should comfortably clear our suggested minimum of 3m x 2.9m.
Consider another size if...
Your room falls short of the 3m x 2.9m we suggest for this size, or you rarely share the bed. We'd recommend the UK king instead: it is 30cm narrower, the same length, and needs a room of at least 2.7m x 2.9m.
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FAQ's
What room size do I need for the Arthur Sleep Cool Pocket Mattress in a UK super king?
We suggest a room of at least 3m x 2.9m, and a little more than that feels comfortable in practice. That allows you to walk around the bed and open drawers without squeezing past. Measure the room before ordering, and check door swing and any tight landing turns while you are at it.
Is the UK super king worth it over the UK king for this mattress?
The UK super king is 30cm wider than the UK king, and the two are the same length. That extra width is the difference between sleeping close by default and sleeping close by choice. If your room clears 3m x 2.9m and you share every night, the added space is usually the better buy.
How much space does each person get on a super king Arthur Sleep Cool Pocket?
Two people sharing get 90cm each, the same width each of you would have on a UK single. In practice that means you can stretch out, change position or let a child settle between you without anyone ending up on the edge of the mattress.
Does a super king reduce partner disturbance on a pocket spring mattress?
Yes, on two counts. The 800 pocket springs compress individually, which limits how far movement travels through the mattress, and the 180cm width puts physical distance between you as well. For a genuinely restless partner, that distance often does more than any comfort layer could.
Where can I buy the Arthur Sleep Cool Pocket Mattress in a UK super king?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so it is the quickest way to see what this size costs today rather than relying on figures that may be out of date.