Komfi Unity Comfort Luxury Small Double Mattress in a Box
The Komfi Unity Comfort Luxury Mattress in a Box has a soft, high-density Reflex foam top layer over a recycled Ecofoam base, which means a cushioned surface with a deep foam core beneath it.
- Cushioned Reflex foam comfort
- Made with recycled foam
- Removable washable cover
£209.54
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Komfi Unity Comfort Luxury Mattress in a Box
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Mattress details
Mattress
Komfi Unity Comfort Luxury Mattress in a Box
Size
Firmness
Construction
Eco-Friendly
Foam
Rolled
Depth (cm)
20
Layers
2
Layer Details
Reflex HD top layer
A soft, high-density Reflex foam layer. It gives you a cushioned surface with support underneath.
Ecofoam base
A deep base made with recycled and re-engineered foam. It provides the core support and is recyclable at the end of its life.
Layer details from komfi.com product page, October 2026.
Key benefits
- Room to spread out alone: At 30cm wider than a UK single, you can sleep diagonally or starfish without an arm hanging off the edge.
- Kinder to compact rooms: Being 15cm narrower than a UK double can be the difference between a wardrobe door opening fully and catching on the mattress corner.
- Fits awkward access: It comes vacuum packed in a roll, which means a twisting staircase or tight landing in a loft conversion is far less of a problem.
- Fine for occasional guests: Two people can share for a weekend visit, although nightly couples will find a UK small double a little snug.
- Easy bedding to find: 4ft is a standard UK size, so small double fitted sheets are easy to buy and a regular double duvet covers it comfortably.
This size suits you if...
You sleep alone but feel cramped on a single, your bedroom is compact and a full double would eat the walking space, or you're furnishing a spare room where friends or family stay as a couple a few nights a year.
Consider another size if...
You share the bed with a partner every night and want space to settle without touching. We'd recommend the UK double instead, which gives 67.5cm each and needs at least 2.6m x 2.8m.
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FAQ's
Will a UK small double Komfi Unity Comfort Luxury fit in a small bedroom?
We suggest allowing at least 2.4m x 2.8m for a UK small double, which leaves space to walk around the bed and open drawers. In a box room, measure where the door swings before you buy. The mattress arrives rolled, so getting it into the room itself is rarely the hard part.
Can two adults sleep on a Komfi small double every night?
It works for occasional stays, but most couples sharing nightly will feel short on space. If you sleep together every night, the UK double gives 67.5cm each and is the more comfortable choice, provided your room meets our suggested 2.6m x 2.8m.
Is a UK small double a good upgrade for a teenager outgrowing a single?
Yes for width, as it's 30cm wider than a UK single, which means far more room to turn over. The length stays the same at 190cm, or 6ft 3in, so a very tall teenager won't gain any legroom from the UK small double.
What size sheets and duvet fit the Komfi Unity Comfort Luxury small double?
Buy small double (4ft) fitted sheets, as standard double sheets will sit loose and wrinkle. A regular double duvet gives good overhang. The mattress is 20cm deep, so check the sheet's pocket depth covers that before buying.
Should I choose the Komfi Unity small double or double?
Pick the UK small double if you sleep alone or your room is under our suggested 2.6m x 2.8m for a UK double. The UK double is 15cm wider at the same length, and that extra width matters most when two people share every night.