Last seen for £319 at Mattress Man on 24th October 2026
Silentnight Special Sleep King Size Mattress
The Silentnight Special Sleep is one of the more affordable routes into a Silentnight mattress, using the brand's Miracoil spring system.
- Firm feel for back & front sleepers
- Reinforced edges for more sleeping area
- Rotate head-to-toe, no flipping
Save with the previous model
Some retailers still sell the earlier version of this mattress for less than the current model's best price.
More available sizes
Last seen for £279 at Mattress Man on 20th October 2026
Last seen for £319 at Mattress Man on 24th October 2026
Last seen for £379 at Mattress Man on 20th October 2026
Last seen for £279 at Mattress Man on 6th November 2026
Last seen for £209 at Mattress Man on 5th November 2026
Mattress details
Mattress
Silentnight Special Sleep Mattress
Size
Firmness
Firm
Construction
Open Coil Spring
Depth (cm)
Layers
2
Layer Details
Comfort layer
Eco Comfort Fibre fillings sit on top of the springs. This is a simple fibre layer rather than foam, so expect a firm, fairly traditional surface rather than a deep, hugging one.
Spring system
A Miracoil open coil system with no roll-together and reinforced edges for more sleeping area. It gives you a firm, supportive base, and the stronger edges mean you can use more of the bed's width.
Layer details from mattressman.co.uk and robertdyas.co.uk product pages, October 2026.
Key benefits
- Proper space for two: With 75cm each for two people sharing, you can both settle into your own half rather than negotiating the middle.
- Length for taller sleepers: At 200cm long, anyone approaching six foot gets their feet on the mattress instead of hanging off the end.
- Zoned support across the full width: The Miracoil system runs zoned support through the mattress, which means your hips and shoulders get resistance wherever you settle across that 150cm.
- A stable surface for different schedules: The firm feel keeps the surface steady, helpful when one of you gets up hours before the other, although Miracoil transfers more movement than pocket springs would.
- An affordable route to king size: The Special Sleep is one of Silentnight's more modestly priced designs, so upgrading from a smaller size costs less than it would with most brands.
This size suits you if...
You share the bed every night and have outgrown the elbow-to-elbow feel of a smaller mattress, you or your partner are tall enough that the 200cm length matters, or you both prefer a firm, stable surface that holds you up rather than cradles you. It also suits couples on different schedules who want a bed steady enough that early alarms disturb the later riser a little less.
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. In either case we'd recommend the UK double instead, which needs a room of at least 2.6m x 2.8m.
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FAQ's
Is a UK king Silentnight Special Sleep good for couples?
Yes, with a caveat. The 150cm width gives you 75cm each for two people sharing, and the firm Miracoil support stays consistent across the full surface. The caveat is motion transfer: zoned springs pass on more movement than pocket springs, so a restless partner will be felt slightly more than on a pocket-sprung king.
Will the Silentnight Special Sleep UK king fit in my bedroom?
The mattress itself is 150 x 200cm, or 5ft x 6ft 6in. We suggest a room of at least 2.7m x 2.9m so you can walk round both sides and open drawers comfortably. If your room is tighter than that, the UK double works in rooms from 2.6m x 2.8m.
Is the UK king long enough for someone over six foot?
It helps considerably. The UK king is 10cm longer than the UK double at 200cm, and that extra length is often the real reason taller sleepers upgrade, more so than the width. If height is your only concern, the length gain matters more than the 15cm of extra width.
Should I choose the king or super king in this mattress?
The UK king is 30cm narrower than the UK super king, and both are the same 200cm length. The UK super king suits couples who want maximum separation, but it needs a room of at least 3m x 2.9m. For most couples the UK king is the more practical fit.
Does the firm feel change in the king size?
No, firmness is the same across every size of the Special Sleep. What changes in the UK king is how you experience it as a couple: with 75cm each, you can each find your own position on that firm surface, rather than compromising around each other as you would on a narrower mattress.