MattressNextDay Classic Memory Foam King Size Mattress
The MattressNextDay Classic is an all-foam mattress with a medium firm feel, made in the UK by an NBF-approved manufacturer.
- Eases pressure at shoulders & hips
- Medium-firm support for back sleepers
- 5-year guarantee
£299
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MattressNextDay Classic Memory Foam Mattress
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Mattress details
Mattress
MattressNextDay Classic Memory Foam Mattress
Size
Firmness
Medium Firm
Construction
Foam
Memory Foam
Depth (cm)
20
Layers
3
Layer Details
EcoFoam®
A thick layer of 100% recycled and re-engineered foam that responds to your body's natural warmth, moulding to your shape. In practice this means pressure relief exactly where you need it, at your hips and shoulders.
Reflex Foam
A firm supportive layer that gives the mattress its medium firm feel, which means your spine stays aligned rather than dipping. It's what provides the orthopaedic-style support.
Memory Foam
A final cushioning layer of memory foam sits nearest to you. It adds a snuggly, softer surface feel over the firmer core.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Space for two to sleep separately, together: At 75cm each for two people sharing, you can stretch out or curl up without negotiating territory in the small hours.
- Foam that keeps movement to itself: Memory foam absorbs motion rather than transmitting it, which means an early alarm on one side is less likely to wake the other.
- Extra length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, a welcome difference if either of you is approaching six foot.
- A meaningful step up from a double: The UK king is 15cm wider than the UK double, giving 7.5cm more each, which sounds modest but is felt every night.
- Room for the extras: If the dog treats the bed as its own, or you're propping pillows through pregnancy, the added width stops one sleeper paying for it.
This size suits you if...
You share the bed every night and the UK double has started to feel cramped, especially if one of you is tall and wants that 200cm length. It also makes sense if you and your partner keep different hours, since the foam's motion absorption plus the extra width means one person getting up hours earlier is far less disruptive.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king. In that case we'd recommend the UK double instead, which still sleeps two and needs a smaller room, at least 2.6m x 2.8m.
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FAQ's
Is the MattressNextDay Classic in a UK king big enough for two adults?
Comfortably, yes. The UK king gives 75cm each for two people sharing, so both of you can change position without brushing elbows. Across a medium firm foam mattress like this one, that width also means each sleeper settles into their own contour rather than rolling towards a shared dip.
What room size do I need for the MattressNextDay Classic king?
We suggest at least 2.7m x 2.9m for a UK king, with more feeling noticeably easier to live with. That allowance covers walking space and bedside tables on both sides. New build master bedrooms can be tighter than they first appear once wardrobes go in, so measure with furniture in place.
Will the UK king size help if my partner gets up earlier than me?
It should. Two things work in your favour here: the 75cm each of width means you're less likely to be jostled in the first place, and the all-foam construction absorbs movement rather than passing it across the bed. Couples on different schedules are exactly who this size suits.
Is the UK king version long enough for someone over six foot?
At 200cm, the UK king is 10cm longer than the UK double, and that length is often the real reason taller sleepers upgrade. If either of you finds your feet reaching the end of a 190cm mattress, this size solves it without moving to a wider footprint than most rooms can take.
How much more space does the king give than the double?
The UK king is 15cm wider and 10cm longer than the UK double. In sharing terms, the UK double gives 67.5cm each while the UK king gives 75cm each, so you gain 7.5cm of personal width. That's roughly the difference between sleeping shoulder to shoulder and each having your own zone.