Silentnight Double Sided Miracoil Super King Mattress
The Silentnight Double Sided Miracoil is a straightforward sprung mattress from one of the UK's best-known bedmakers.
- Zoned support for hips & shoulders
- Breathable fibres keep you cooler
- Double-sided to even out wear
£311
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Silentnight Double Sided Miracoil Mattress
More available sizes
Mattress details
Mattress
Silentnight Double Sided Miracoil Mattress
Size
Firmness
Medium Firm
Construction
Open Coil Spring
Depth (cm)
24
Layers
3
Layer Details
Cover
A soft knitted cover that is highly breathable, which means less heat trapped at the surface. It feels soft to the touch rather than stiff or papery.
Comfort Fillings
Air Plus fibres, breathable comfort fibres that encourage airflow through the mattress. In practice that helps keep the sleep surface feeling fresher through the night.
Support System
Silentnight's Miracoil spring system, a zoned open coil unit designed to support all parts of the body with individual sleeping zones. The no roll-together design means you are less likely to drift into your partner's side.
Base Note
The mattress is double sided, so you can flip it to even out wear over time. It arrives flat rather than rolled and boxed, which spares the springs any compression.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- 90cm of width each: Two sharers get 90cm apiece, which means a fidgety partner is far enough away that the zoned springs rarely get tested.
- No roll-together across a wide bed: The Miracoil system is designed to stop you drifting into your partner's side, useful when you have paid for all this space to keep it.
- Room for the whole household: Children who appear at 3am, or a dog that treats the bed as routine, can join you without anyone losing their share of the 180cm width.
- Firmer support that holds its edge: The medium-firm zoned coils suit back and front sleepers, so a child perched near the side does not tip the whole surface.
- Flippable to spread the wear: The double sided build lets you turn the mattress to even out use, sensible when a bed this size is shared by more than two.
This size suits you if...
You share the bed every night and a UK king still feels crowded, children or pets regularly join you and you want everyone to keep a proper share, or you have a large master bedroom where a smaller bed would look lost. Allow at least 3m x 2.9m of floor space, with around 3.5m x 3.2m feeling comfortable.
Consider another size if...
Your bedroom is smaller than our suggested 3m x 2.9m minimum, or your landing turns tightly. 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
How big is the Silentnight Double Sided Miracoil in a UK super king?
It measures 180 x 200cm, or 6ft x 6ft 6in. For two people sharing, that is 90cm each, the widest sleeping space stocked as standard by UK retailers. The 200cm length also gives taller sleepers 10cm more legroom than a UK double.
Does the super king Silentnight Miracoil arrive rolled in a box?
No, it arrives flat, which spares the springs any compression but does mean manoeuvring a 180 x 200cm mattress through your home. Before ordering, measure your stairway, any landing turns and the bedroom door swing, since this is the size where tight corners genuinely bite.
Is a super king Silentnight Miracoil worth it for a restless partner?
This is where the size makes the biggest difference. With 90cm each, you are simply too far apart to feel most movement, and the Miracoil no roll-together design keeps you from drifting towards the middle. Distance does more for disturbed sleep than any comfort layer can.
How hard is it to flip a super king mattress?
The double sided design means you should flip it periodically to even out wear, and at 180cm wide this is realistically a two-person job. If you live alone or struggle with lifting, factor that in before choosing this size.
Where can I buy the Silentnight Double Sided Miracoil in a UK super king?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so it is worth checking back if you are not buying today, as larger sizes like the UK super king are where price gaps between sellers tend to be widest.