Last seen for £259 at Silentnight on 2nd September 2026
Silentnight Just Sleep Relax Single Mattress
The Silentnight Just Sleep Relax is one of Silentnight's more affordable options, available in UK Single, Double and King.
- Moulds closely to your body
- 3-zone support for better alignment
- Classic memory foam feel
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 £259 at Silentnight on 2nd September 2026
Last seen for £359 at Silentnight on 2nd September 2026
Last seen for £299 at Silentnight on 2nd September 2026
Mattress details
Mattress
Silentnight Just Sleep Relax Mattress
Size
Firmness
Construction
Depth (cm)
Layers
Layer Details
Key benefits
- Fits compact rooms: At 90cm wide it leaves floor space free in small bedrooms, and we suggest a room of at least 2.1m x 2.8m.
- Sensible for a child's room: A budget single from a familiar UK brand suits a bedroom where the bed shares space with a wardrobe, a desk and toy storage.
- Good spare room logic: A room that doubles as an office needs a bed that takes up little space, and the UK single is the narrowest standard adult size.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm single duvet fit, and both are the cheapest and most widely stocked of any size.
- Low outlay for occasional use: For a student room or first flat where the frame is already provided, this keeps the mattress cost down without buying from an unknown label.
This size suits you if...
You're buying for a child or teenager's bedroom, you sleep alone and want to keep floor space free in a small room, or you're kitting out a spare room or student flat where the bed gets occasional rather than nightly use and a low price matters more than detailed specs.
Consider another size if...
You're an adult sharing the bed, or you sleep alone but move around a lot at night. The Silentnight Just Sleep Relax also comes in a UK double, which is 45cm wider; allow a room of at least 2.6m x 2.8m for it.
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FAQ's
What size is the Silentnight Just Sleep Relax UK single?
It measures 90 x 190cm, which is 3ft x 6ft 3in, the standard UK one-person size. Standard single fitted sheets and a single duvet (135 x 200cm) fit it, so there's no need for special bedding.
Will the UK single Just Sleep Relax fit in a small bedroom?
Almost certainly. We suggest a minimum room of 2.1m x 2.8m for a UK single, which is smaller than the guidance for any other standard size. That leaves space in most children's rooms for a wardrobe and a desk alongside the bed, and it suits a spare room that also works as an office.
Can I use the Just Sleep Relax single on a bunk or mid sleeper?
The 90 x 190cm footprint matches standard UK bunk and mid-sleeper frames. The complication is depth: Silentnight doesn't publish detailed specifications for this model, and raised frames have maximum depth limits for guard rail safety. Check the depth on the retailer listing against your frame's stated maximum before ordering.
Is the UK single big enough for an adult?
For a single adult who sleeps fairly still, yes, and it's the sensible pick for a guest bed or student room. If you spread out at night, the Silentnight Just Sleep Relax also comes in a UK double, which is 45cm wider than the UK single and the same length.
Should I choose the single or the double for a guest room?
If the room only hosts one guest at a time, the UK single frees up floor space and keeps costs down. The UK double is 45cm wider and needs a room of at least 2.6m x 2.8m by our guidance, so measure first. Two singles can also suit a guest room that hosts pairs who aren't couples.