Silentnight Comfort Breathe 1200 Super King Mattress
The Silentnight Comfort Breathe 1200 is a medium/firm pocket sprung mattress with a breathability-first design.
- Breathable fibres for hot sleepers
- Minimises partner disturbance
- 60-night trial & 5-year guarantee
£729
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Silentnight Comfort Breathe 1200 Mattress
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Mattress details
Mattress
Silentnight Comfort Breathe 1200 Mattress
Size
Firmness
Medium Firm
Construction
Foam
Pocket Spring
Memory Foam
Depth (cm)
25
Layers
5
Layer Details
Sleep surface
A naturally hypoallergenic fabric surface that's soft against the skin. A sensible choice if allergies or sensitive skin are a concern.
Comfort Breathe®
Silentnight says these fibres are 15x more breathable than standard memory foam, promoting airflow and regulating temperature. In practice, that means less overnight heat build-up, which hot sleepers will appreciate.
1200 Mirapocket spring unit
1200 pocket springs respond individually to your body's movements, which means support where you need it rather than a one-size-fits-all push-back. The zoning is designed to aid spinal alignment, helpful if back or neck pain is part of your mornings.
Protective Layer
This layer spreads pressure from the spring unit across the mattress, which means less localised wear over time. It's there for longevity rather than feel.
Durable case
A soft but hard-wearing outer case designed to keep the mattress comfortable for years. Unglamorous, but it matters for how the mattress ages.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- Distance from a fidgety partner: With 90cm each for two people sharing, most of their tossing happens too far away to reach you in the first place.
- Springs that keep movement local: The 1200 Mirapocket springs respond individually, which means the motion that does travel across the mattress is softened before it gets to your side.
- Room for the whole household: When children or a large dog treat your bed as theirs, this size means everyone still gets a workable share rather than you clinging to the edge.
- Cooler across a bigger surface: The Comfort Breathe fibre layer promotes airflow rather than trapping heat, and at this width two warm bodies aren't pressed together making things worse.
- Suits a large master bedroom: In a period property or generous new build master, a UK super king fills the space properly where a UK king can look undersized.
This size suits you if...
You share every night and want the most space a standard UK size offers, your sleep is regularly broken by a partner who moves a lot, or children and pets join you often enough that a UK king feels crowded. Your bedroom should measure at least 3m x 2.9m by our guidance, and around 3.5m x 3.2m feels right, so this suits a genuinely large room.
Consider another size if...
Your bedroom falls short of the 3m x 2.9m we suggest as a minimum, or the bed would dominate the room. We'd recommend the UK king instead: it's 30cm narrower, the same length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
Is a super king Silentnight Comfort Breathe 1200 too big for my bedroom?
It depends on the room. We suggest at least 3m x 2.9m as a minimum, with around 3.5m x 3.2m feeling comfortable once you allow for wardrobes and walking space. Measure the door swing too. If your room is tighter than that, the UK king is 30cm narrower and needs at least 2.7m x 2.9m.
How much space does each person get on the super king Comfort Breathe 1200?
Two people sharing get 90cm each, the most of any standard UK size. Combined with the 1200 Mirapocket springs, which respond to movement individually rather than transmitting it across the bed, a partner who shifts position all night becomes much easier to sleep through.
Is the Comfort Breathe 1200 in a super king good for co-sleeping with children?
It's the size we'd point families towards. At 180cm wide there's room for a child who arrives mid-morning without anyone hanging off the edge, and the pocket springs limit how much their wriggling travels. The medium/firm feel also holds its shape well with extra bodies on it, though very light children will barely dent it.
Will the super king Comfort Breathe 1200 get up a narrow staircase?
This is the size where stairs bite. Pocket sprung mattresses shouldn't be folded, so measure your landing turns and doorways against 180 x 200cm before ordering. This model isn't sold as zip and link halves, so if access is genuinely tight, sizing down to the UK king, at 30cm narrower, may be the safer call.
What's the difference between the king and super king Comfort Breathe 1200?
Width only. The UK super king is 30cm wider than the UK king, and the two are the same length. The construction, depth and medium/firm feel don't change. The extra width is what buys you undisturbed sleep next to a restless partner, at the cost of a bigger room requirement and pricier bedding.