Silentnight Comfort Breathe 1400 King Size Mattress
The Silentnight Comfort Breathe 1400 is a firm pocket sprung mattress with 1400 Mirapocket springs in individual pockets.
- Firm support for back & front sleepers
- Breathable fibres help you stay cool
- 60-night trial & 5-year guarantee
£581.60
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Silentnight Comfort Breathe 1400 Mattress
More available sizes
Mattress details
Mattress
Silentnight Comfort Breathe 1400 Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Depth (cm)
28
Layers
4
Layer Details
Hand tufted sleep surface
A hand tufted top made from naturally hypoallergenic fabric, which means the fillings stay in place and sensitive sleepers get a gentler start. Silentnight describes this as a softer sleep surface, taking a little of the edge off the firm feel beneath.
Comfort Breathe™ fibres
A second layer of breathable fibres for increased airflow and improved temperature regulation, which means heat is less likely to build up around you overnight. Silentnight says it also adds firmer pressure relief.
1400 Mirapocket springs
The springs sit in individual pockets and respond independently to your body's movements, which means zoned support and better spinal alignment rather than a uniform surface. The 1400 count is for the king size, with counts adjusted pro rata for other sizes.
Durable case
A soft, hard-wearing outer case built to keep the mattress comfortable over the years. The underside is a polypropylene and polyester blend, with a polyester-led side border.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- The full 1400 spring count: Silentnight's 1400 figure applies to the king size specifically, so you get the complete spring count rather than a pro rata reduction.
- Less partner disturbance: The Mirapocket springs move independently, which means an early alarm on one side is far less likely to travel across 150cm of mattress.
- Length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, so feet stay on the mattress rather than at its edge.
- Cooler for two: Two bodies raise the temperature under a duvet, and the Comfort Breathe fibre layer is designed to move that heat away rather than trap it.
- Firm support across the width: The pocket springs give each of you support shaped to your own body, so a heavier and lighter partner are held separately rather than rolling together.
This size suits you if...
You share the bed every night and keep waking when your partner turns or gets up hours before you, or one of you is tall enough that a 190cm mattress leaves feet hanging. It also suits couples who both want firm support without compromising, since each side of the bed responds to its own sleeper. Allow at least 2.7m x 2.9m of floor space.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest, which is common in a new build master once the wardrobes go in. We'd recommend the UK double instead: it needs at least 2.6m x 2.8m.
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FAQ's
Is the Silentnight Comfort Breathe 1400 in a UK king good for couples?
Yes, provided you both like a firm feel. The 150cm width gives you 75cm each for two people sharing, and the pocket springs respond independently, so movement on one side is less likely to wake the other. Lighter side sleepers may find it a little unforgiving around the shoulders, so factor in how you each sleep.
Does the 1400 spring count apply to the UK king size?
Yes, and this is the one size where it does exactly. Silentnight counts its Mirapocket springs on the king, then adjusts pro rata for other sizes, so smaller sizes carry fewer springs and the UK super king carries more. Buying the UK king means the headline figure describes the mattress you actually receive.
What room size do I need for the Silentnight Comfort Breathe 1400 in a UK king?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable, and that guidance is ours rather than Silentnight's. It leaves room to walk round the bed and get in and out on both sides, which matters if you're recovering from an injury or in the later stages of pregnancy.
Is the UK king long enough for someone over six foot?
At 200cm, it should be. That's 10cm longer than the UK double, and for anyone approaching or past six foot the extra length is often the upgrade that matters more than the width. The firm pocket sprung support runs the full length, so taller sleepers aren't left with softer support at the foot end.
Should I get this mattress in a UK king or a UK double?
If you share and your room allows it, the UK king. It's 15cm wider and 10cm longer than the UK double, a difference you notice every night, and on a firm mattress like this the extra width means you each settle into your own supported zone. Choose the UK double only where space is genuinely tight.