Komfi Unity Deluxe King Size Mattress
The Komfi Unity Deluxe is a firm all-foam mattress pairing a reflex foam layer with an Ecofoam layer made from recycled materials.
- Firm, level support for your back
- Handcrafted in the UK
- Made with recycled foam
£225
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Komfi Unity Deluxe Mattress
More available sizes
Mattress details
Mattress
Komfi Unity Deluxe Mattress
Size
Firmness
Firm
Construction
Foam
Memory Foam
Depth (cm)
17
Layers
2
Layer Details
Reflex Foam
A flexible reflex foam layer that supports spinal alignment, which means your back stays level rather than sagging into the mattress. It's the backbone of the Unity Deluxe's firm feel.
Ecofoam
Made from recycled materials, this layer lowers the mattress's carbon footprint while adding a softer, cradling comfort above the firmer base. It takes a little edge off the firmness without undermining the support.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Room to sleep apart, together: At 75cm each for two people sharing, you can both change position without brushing elbows, useful when one of you gets up hours before the other.
- Firm foam limits movement transfer: The reflex foam base keeps the surface stable, so a partner sliding out at 5am is less likely to wake you than on a bouncier mattress.
- Extra length for taller sleepers: The UK king is 10cm longer than the UK double, which matters far more than width if one of you is approaching six foot.
- Easier to handle than most kings: The shallow 17cm profile keeps a big 150 x 200cm mattress manageable on stairs and around tight landings.
- A lower-impact choice: The Ecofoam layer is made from recycled materials, so upgrading to a bigger mattress carries a smaller carbon footprint than standard foams.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially if one of you keeps different hours or a dog has claimed a corner as routine. It also suits taller sleepers who want that extra 10cm of length over the UK double, and anyone upgrading size on a tight budget who values firm support over a plush, sink-in feel.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest for a UK king, particularly once wardrobes are in. The UK double would suit you better, needing at least 2.6m x 2.8m while still sleeping two.
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FAQ's
Is the Komfi Unity Deluxe in a UK king big enough for two people?
Yes, comfortably. At 150 x 200cm you get 75cm each for two people sharing, and the firm reflex foam keeps the surface stable, so one person shifting or getting up early is less likely to disturb the other. Heavier couples may actually prefer the firm feel, as there's less sinkage than on softer foams.
Will a UK king Komfi Unity Deluxe fit in my bedroom?
We suggest a room of at least 2.7m x 2.9m for a UK king, and closer to 3.2m x 3.2m if you want bedside tables on both sides and easy walking space. New build master bedrooms can be tighter than they look once wardrobes go in, so measure with furniture in place before you commit.
Is the Komfi Unity Deluxe king worth it over the double?
The UK king is 15cm wider and 10cm longer than the UK double. The width is what couples notice night to night, while the length is the real win if either of you is tall. Given the Unity Deluxe sits at the budget end of the market, the step up costs less than it would on most mattresses.
Is a king size foam mattress hard to move upstairs?
Less so than most. The Unity Deluxe is only 17cm deep and all foam, so it flexes around banisters and doorways more easily than a sprung mattress of the same 150 x 200cm footprint. Two people will still make lighter work of it, as a king is an awkward shape however shallow it is.
Where can I buy the Komfi Unity Deluxe in a UK king?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them, so it's worth checking back if you're not buying today. Stock of specific sizes can move around, and the UK king is a popular size, so availability at a given retailer isn't guaranteed week to week.