Silentnight Miracoil Ortho Super King Mattress
The Silentnight Miracoil Ortho is a firm mattress built around Silentnight's zoned Miracoil® spring system, topped with breathable Eco Comfort fibres made partly from recycled plastic bottles.
- Firmer support under your hips
- Supports right to the edge
- 60-night trial & 5-year guarantee
£439
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Silentnight Miracoil Ortho Mattress
More available sizes
Mattress details
Mattress
Silentnight Miracoil Ortho Mattress
Size
Firmness
Firm
Construction
Open Coil Spring
Depth (cm)
24
Layers
2
Layer Details
Eco Comfort Fibres
A comfort layer made with Silentnight's Eco Comfort fibres, partially made from recycled plastic including bottles. It is breathable, helps regulate temperature and reduces moisture build-up, which means you should feel less clammy overnight.
Miracoil® springs
Silentnight's Miracoil® support system gives zoned support where your body needs it most, so heavier areas like your hips get firmer resistance. It also supports right to the edge of the bed and is designed to limit partner disturbance when one of you moves.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- 90cm each for two sharers: With 90cm each for two people sharing, a restless partner can toss and turn well out of reach, which distance does better than any comfort layer.
- Room for night-time visitors: When a child pads in at 3am, or the dog treats your bed as routine, the extra width means everyone still gets a workable share.
- Edge support you can actually use: Silentnight says the Miracoil® system supports right to the edge, so all 180cm of width is usable rather than a no-go strip on each side.
- Firm zoned support across the full width: The Miracoil® springs concentrate resistance under heavier areas like your hips, so both sleepers get aligned support even when they weigh quite different amounts.
- A big bed that stays affordable: Super kings usually sit at the expensive end, but this is a simple two-layer build, so you get the space without the premium construction costs.
This size suits you if...
You share the bed every night and want the most sleeping space a standard UK size offers, your children or pets regularly join you and a UK king feels crowded, or you have a large master bedroom where a smaller bed would look undersized. It also suits couples where one sleeper is genuinely restless, since 90cm each puts real distance between you.
Consider another size if...
Your bedroom is under our suggested 3m x 2.9m minimum, or you sleep alone and would rather not wrestle super king bedding. We'd recommend the UK king instead: it is 30cm narrower, the same length, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
Is the Silentnight Miracoil Ortho super king big enough for a family sharing?
It is the most practical choice for it. At 180 x 200cm you get 90cm each for two people sharing, so when a child wanders in overnight there is still a reasonable share for everyone. The firm Miracoil® springs also hold their shape under uneven, shifting weight better than a soft mattress would.
Does the Miracoil Ortho in a super king help with a restless partner?
Yes, mostly through sheer distance. With 90cm each, movement on one side is simply further away, and Silentnight says the Miracoil® system is designed to limit partner disturbance too. The firm feel helps as well, since a firmer surface transfers less bounce than a soft one when someone rolls over.
Will the Silentnight Miracoil Ortho super king fit in my bedroom?
We suggest at least 3m x 2.9m for a UK super king, and closer to 3.5m x 3.2m feels comfortable once you add bedside tables and walking space. Before ordering, check door swings, landing turns and stairs: at 6ft x 6ft 6in this is a large single unit to manoeuvre upstairs.
Is the Miracoil Ortho super king worth it over the UK king?
If you regularly share with children, pets or a restless partner, yes: the UK super king is 30cm wider than the UK king, and the two are the same length, so all the gain is in elbow room. In a room under our suggested 3m x 2.9m, the UK king is the more sensible buy.
Can you sleep near the edge of the super king Miracoil Ortho?
Silentnight says the Miracoil® system supports right to the edge of the bed, which matters more at this size than any other. A super king only earns its extra width if you can spread across all of it, and firm edges mean neither sleeper ends up huddling toward the middle.