KomfiMed Ortho Firm King Size Mattress
The KomfiMed Ortho Firm is a 25cm all-foam mattress with a firm feel, which means solid, even support rather than a cushioned sink-in surface.
- Firm, responsive on-top feel
- Minimises partner disturbance
- Cooling gel helps regulate temperature
£728
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KomfiMed Ortho Firm Mattress
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Mattress details
Mattress
KomfiMed Ortho Firm Mattress
Size
Firmness
Firm
Construction
Foam
Gel
Depth (cm)
25
Layers
5
Layer Details
Microquilted cover
A micro-quilted cover gives the sleep surface a smooth, soft finish. It takes a little of the edge off an otherwise firm mattress.
Castellated foam
This medically-proven castellated foam layer minimises motion transfer. In practice, that means less disturbance when a partner turns over in the night.
TrueGel Technology
Komfi's naturally cooling TrueGel technology helps regulate your temperature. Foam can run warm, so this layer works against that tendency.
Reflex Foam
A core reflex support layer provides a firm, responsive foundation. This is where the mattress gets its orthopaedic-style, on-top-of-the-bed feel.
Ecofoam
The base is a resilient, durable Ecofoam layer made from 100% recycled and re-engineered foam. It's also naturally dust-mite resistant, which allergy sufferers will appreciate.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Room to sleep apart, together: The UK king is 15cm wider than the UK double, which means fewer accidental elbows and less negotiating over the middle of the bed.
- Motion transfer matters more at this width: The castellated foam layer reduces movement travelling across the mattress, so a partner getting up early is less likely to wake you.
- Length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, useful if one of you is approaching six foot and tired of cold feet off the end.
- Firm support across the full surface: The reflex foam core gives the same solid, on-top feel edge to edge, so neither sleeper drifts into a softer middle.
- Cooling help for two: Two bodies raise the temperature under one duvet, and TrueGel technology is designed to work against foam's tendency to run warm.
This size suits you if...
You share the bed every night and a double has started to feel cramped, you both prefer a firm surface or have been advised to try one for back support, or one of you keeps different hours and you want their comings and goings to disturb you less. It also suits couples where one partner is tall enough to appreciate the extra length over a double.
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 and don't need the width. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is a UK king big enough for a couple on a firm mattress?
Yes, comfortably for most. You get 75cm each for two people sharing, and because the KomfiMed Ortho Firm holds you on top of the surface rather than letting you sink, you tend to stay in your own space. If you both sprawl, the UK super king is 30cm wider and worth a look.
Will I feel my partner moving on the KomfiMed Ortho Firm king?
Less than you might expect from a firm mattress. The castellated foam layer is designed to minimise motion transfer, and at 150cm wide there's simply more distance between you than on a double. If one of you gets up hours before the other, that combination helps.
Is the KomfiMed Ortho Firm king long enough for someone over six foot?
At 200cm (the UK king is 5ft x 6ft 6in), it's 10cm longer than the UK double, which is the difference between feet hanging off the end and lying flat. Anyone well past six foot should still measure carefully, but for most taller sleepers the length is the quiet win of this size.
What size room do I need for the KomfiMed Ortho Firm in a king?
We suggest allowing at least 2.7m x 2.9m, with more feeling noticeably easier to live with. New build master bedrooms can be tighter than they look once fitted wardrobes go in, so measure the usable floor space, and leave enough clearance to walk round both sides of the bed.
Where can I buy the KomfiMed Ortho Firm mattress 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 before you buy. Owner feedback for this mattress is still sparse, so you're buying more on the specification than on a long history of reviews.