Wentworth Mercer Mercer 3000 Pocket Pro Super King Mattress
The Wentworth Mercer Mercer 3000 Pocket Pro Mattress combines a pocket spring core with extra layers of mini springs and a double-sided, flippable build, which means firm, bouncy support you can turn to even out wear.
- Firm support for back & front sleepers
- Springs adapt to each sleeper
- Flip it to even out wear
£945
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Wentworth Mercer Mercer 3000 Pocket Pro Mattress
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Mattress details
Mattress
Wentworth Mercer Mercer 3000 Pocket Pro Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Depth (cm)
32
Layers
5
Layer Details
Wool, cashmere and silk layers
Two layers of a wool, cashmere and silk blend sit at the top. They add a cosy, soft-touch surface over the firm feel beneath.
Polyester fibre layers
Two layers of polyester fibres add to the comfort layer. They give a little extra cushioning between the surface and the springs.
Cotton and polyester layers
A blend of cotton and polyester forms two moisture-wicking layers. They help draw moisture away as you sleep.
Mini pocket springs
Two layers of 1000 mini springs add a bouncy feel. You get a springier, more responsive surface over the core.
Pocket spring core
A core of 1000 pocket springs adapts to the movement and weight of each sleeper. That means support tailored to your body, and the firm feel is rooted here.
Layer details from mattressonline.co.uk product page, November 2026.
Key benefits
- 90cm each for two sharing: Each of you gets a full 90cm, which means a partner who fidgets or gets up early is far less likely to disturb you.
- Room for late-night visitors: A child climbing in after a bad dream still leaves both adults a usable share, which a smaller bed rarely manages.
- Firm support across the full width: The firm pocket spring core adapts to each sleeper's weight, so a heavier partner on one side doesn't drag a lighter one towards the middle.
- Fills a large room properly: In a period property or a generous master bedroom, the 6ft x 6ft 6in footprint looks in proportion where a UK king can seem a little lost.
- Two sides to share the wear: Being double-sided, it can be flipped to spread wear evenly, which helps on a bed this wide where two people press into separate zones every night.
- Space for a large dog: If a big dog sleeps on the bed as a matter of routine, the extra width gives it somewhere to settle without pushing anyone to the edge.
This size suits you if...
You share the bed with someone whose tossing and turning keeps waking you, your children or a large dog often end up in with you, or you have a big master bedroom where a UK king would look undersized.
Consider another size if...
Your bedroom is smaller than our suggested 3m x 2.9m, or your stairs and landing turns are tight. We'd recommend the UK king instead, which needs at least 2.7m x 2.9m.
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FAQ's
Is a Mercer 3000 Pocket Pro super king big enough for two adults and a child?
For a child who wanders in occasionally, yes. Two adults get 90cm each, so a small child can usually tuck in between without anyone hanging off the edge. If it happens most nights, the firm surface stays supportive across the width, but a nightly family of three will still feel snug rather than spacious.
What size bedroom do I need for a UK super king Wentworth Mercer mattress?
We suggest at least 3m x 2.9m for a UK super king, with around 3.5m x 3.2m feeling more comfortable once bedside tables and wardrobe doors are in place. In a loft conversion, the roof slope usually decides which wall the headboard goes against, so measure the full-height floor area rather than the whole room.
How much wider is the Mercer 3000 super king than the king?
The UK super king is 30cm wider than the UK king, and the two are the same length. Shared between two people, that works out at 15cm more each, which is the difference you'll feel if your partner tends to sprawl.
Is the super king Mercer 3000 Pocket Pro hard to flip?
It's a two-person job at this size. The mattress is 32cm deep and 180cm wide, so turning it means clearing space around the bed and lifting a wide, heavy panel together. Plan to do it with a helper and check you have room to stand it on its side partway through.
What bedding fits a UK super king Mercer 3000 mattress?
You'll need super king sheets and a 260 x 220cm duvet. At 32cm deep, the mattress needs fitted sheets with deep pockets, so check the stated pocket depth before you buy. Super king bedding also costs more than king sets, which is easy to forget when budgeting for the bed.