Last seen for £619 at Silentnight on 2nd September 2026
Silentnight Just Sleep Calm Single Mattress
The Silentnight Just Sleep Calm sits within Silentnight's Just Sleep range, available in UK Single, UK Double and UK Super King.
- Medium-firm feel for most sleepers
- Fabric surface absorbs body heat
- Support right up to the edges
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 £829 at Silentnight on 2nd September 2026
Last seen for £619 at Silentnight on 2nd September 2026
Last seen for £735 at Silentnight on 24th June 2026
Last seen for £669 at Silentnight on 2nd September 2026
Mattress details
Mattress
Silentnight Just Sleep Calm Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
Layers
Layer Details
Key benefits
- Fits almost any room: At 90cm wide, this size needs only 2.1m x 2.8m of floor space by our guidance, so a compact bedroom or box room still has walking room.
- Room for the rest of childhood: In a child's room the bed shares space with a wardrobe, a desk and toy storage, and a UK single leaves the most floor free for all three.
- Suits shared rooms: Where siblings share, two UK singles plus a walkway fit in rooms that couldn't take anything wider.
- The easiest bedding to buy: Single sheets and a 135 x 200cm single duvet are the cheapest and most widely stocked bedding of any UK size.
- A practical guest option: In a spare room doubling as an office, a UK single keeps the desk in and the guests comfortable, where a UK double would swallow the room.
This size suits you if...
You're buying for a child or teenager moving up from a cot or toddler bed, you sleep alone and want to keep floor space free in a small room, or you're kitting out a spare room, student room or first flat where the frame is already a single.
Consider another size if...
You're an adult who shares the bed, or a restless solo sleeper who wants space to spread out. We'd recommend the UK double instead; it's 45cm wider and the same length, and we suggest a room of at least 2.6m x 2.8m for it.
Similar Mattresses in This Price Range
Did you know? On Mattress Unboxed we have over 1,000 different mattresses to suit all types of sleepers. View all mattresses.
FAQ's
What size is the Silentnight Just Sleep Calm single mattress?
The UK single version measures 90 x 190cm, or 3ft x 6ft 3in. That's the standard UK one-person size, so it fits any standard single bed frame, divan or slatted base without gaps or overhang.
Will the UK single Silentnight Just Sleep Calm fit a bunk or mid sleeper?
The footprint matches standard bunk and mid-sleeper frames, which are built around 90 x 190cm. Raised frames also set a maximum mattress depth for the guard rail to work, and Silentnight doesn't publish a depth for this mattress, so check the retailer's listing against your frame's limit before buying.
Is a UK single big enough for an adult?
For one average-sized adult, yes, and it's the standard choice for student rooms and first flats where the frame is already provided. If you're tall, note the 190cm length is 10cm shorter than a UK king. Broad-shouldered or restless sleepers may prefer the UK double's extra 45cm of width.
How much room do I need for the single Just Sleep Calm?
We suggest at least 2.1m x 2.8m of floor space, which is our own guidance rather than Silentnight's. That allows you to open drawers and walk past comfortably. In a loft conversion, the 90cm width also makes it easier to tuck the bed under the slope where a wider mattress wouldn't sit.
Should I buy a single or a double for a guest room?
It depends on your guests. A UK single suits a room that also works as an office, and two singles handle visiting pairs who'd rather not share. If couples stay regularly and the room allows 2.6m x 2.8m, the UK double of this mattress is 45cm wider and the same length.