Silentnight Memory Cool 1000 King Size Mattress
The Silentnight Memory Cool 1000 is a hybrid mattress that pairs 1000 Mirapocket springs with a graphite-infused Memory Cool foam layer, which means you get the contouring feel of memory foam without as much of the heat it usually traps.
- Graphite foam draws heat away
- Minimises partner disturbance
- 60-night trial & 5-year guarantee
£719
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Silentnight Memory Cool 1000 Mattress
More available sizes
Mattress details
Mattress
Silentnight Memory Cool 1000 Mattress
Size
Firmness
Medium Firm
Construction
Foam
Pocket Spring
Hybrid
Memory Foam
Depth (cm)
29
Layers
2
Layer Details
Memory Cool™
A graphite-infused memory foam that moulds to your body to relieve pressure while actively moving heat away from you. Silentnight says this creates a sleep environment 15% cooler than standard memory foam, which means less of the clammy feeling memory foam is known for.
Mirapocket® springs
1000 pocket springs, each held in its own fabric pocket so it responds to your movement independently. In practice that means zoned support along your body and less motion transfer across the bed.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- Proper space for two: At 150cm wide you get 75cm each for two people sharing, which means you can change position without negotiating for territory.
- Springs that keep the peace: The 1000 Mirapocket springs respond to movement individually, so a partner leaving hours before your alarm is far less likely to wake you.
- Length for taller sleepers: The UK king is 10cm longer than the UK double at 200cm, which means anyone approaching six foot stops sleeping with their feet at the edge.
- Cooler with room to spread: Two people generate heat, so the graphite-infused Memory Cool foam matters more at this size, drawing warmth away where a shared bed tends to build it.
- Room for the dog too: If a pet claims a corner every night, the UK king's extra width means their share stops coming directly out of yours.
This size suits you if...
You share the bed every night and have started to feel the edges of a double, one of you gets up much earlier than the other, or someone in the bed is tall enough to want the full 200cm length. The Medium/Firm feel and independent springs suit couples who want stable support with minimal disturbance, so restless sharing is exactly the situation this size handles.
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. The UK double needs less floor space, we suggest at least 2.6m x 2.8m, and would suit a solo sleeper comfortably.
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FAQ's
Is the Silentnight Memory Cool 1000 UK king big enough for two adults?
Yes, comfortably for most couples. At 150 x 200cm it gives 75cm each for two people sharing, and the 1000 pocket springs respond to each of you separately, so one person shifting or getting up early causes less disturbance on the other side. If one of you sprawls dramatically, the UK super king adds another 30cm of width.
What room size do I need for the Memory Cool 1000 in a UK king?
We suggest allowing at least 2.7m x 2.9m, which leaves enough room to walk around the bed and open drawers without shuffling sideways. New build master bedrooms can be tighter than they look once wardrobes go in, so measure the usable floor space rather than the room dimensions on the plan.
Should I get the Memory Cool 1000 in a UK king or a UK double?
For couples, the UK king is usually the better buy: it's 15cm wider and 10cm longer than the UK double, and that width difference is felt every night rather than occasionally. Choose the UK double if your room is smaller, we suggest at least 2.6m x 2.8m for that size, or if you mostly sleep alone.
Is the UK king Memory Cool 1000 long enough for tall sleepers?
At 200cm, the UK king is 10cm longer than the UK double, which makes a real difference to anyone approaching six foot. The Medium/Firm feel also gives taller, heavier sleepers a stable surface rather than a deep sink. If you're well over six foot, no standard UK size adds more length; the UK super king is the same 200cm, just wider.
Where can I compare prices for the Memory Cool 1000 in a UK king?
Use the price table on this page. The prices shown here are updated as retailers change them, so it reflects what's actually available for this size today rather than a list price. It's worth a quick check across the retailers listed, as the same UK king can vary between them.