Komfi Serenity Comfort Reflex King Size Mattress in a Box
The Komfi Serenity Comfort Reflex Mattress in a Box has a firm reflex foam build with a recycled foam base, which means you get steady, supportive sleep in a mattress that arrives rolled up.
- Firm feel for back sleepers
- Recycled foam in the build
- Washable cover & no flipping
£267.69
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Komfi Serenity Comfort Reflex Mattress in a Box
More available sizes
Mattress details
Mattress
Komfi Serenity Comfort Reflex Mattress in a Box
Size
Firmness
Firm
Construction
Eco-Friendly
Foam
Rolled
Depth (cm)
20
Layers
Layer Details
Key benefits
- More space each: At 75cm per person for two sharing, the UK king gives you each 7.5cm more than the UK double, which means fewer elbows and knees crossing the middle.
- Length for a tall partner: At 200cm, or 6ft 6in, the UK king is 10cm longer than the UK double, so a partner over six foot is less likely to end up with feet over the edge.
- Spring-free for different schedules: This is an all-foam mattress with no springs, so an early riser getting up may cause less bounce on your side than a sprung bed, though Komfi publishes no movement figures.
- Easier to get upstairs: It comes vacuum packed and rolled, which means a full UK king can get round tight landings and up stairs that a flat mattress this size would struggle with.
- Washable cover for a shared bed: The zipped stretch knit cover comes off for machine washing, which is handy if the dog joins you on the bed most nights.
This size suits you if...
You and your partner keep disturbing each other on a UK double, or one of you is tall enough that the extra 10cm of length matters as much as the width, and you both prefer a firm surface to one you sink into.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king once wardrobes and drawers are in. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is the Komfi Serenity Comfort Reflex king size big enough for two?
For most couples, yes. The UK king gives 75cm each for two people sharing, which is 7.5cm more each than the UK double. If one of you sprawls or you're on different schedules, that extra room helps you keep to your own side.
What size bedroom do I need for a UK king Komfi Serenity mattress?
We suggest at least 2.7m x 2.9m for a UK king. New build master bedrooms can feel tighter than the floor plan suggests once fitted wardrobes are in, so measure the clear floor space. If you're under that, the UK double needs at least 2.6m x 2.8m.
Is the Komfi Serenity UK king long enough for a tall person?
The UK king is 200cm long, or 6ft 6in, which is 10cm longer than the UK double. If one of you is over six foot, that extra length is often the bigger upgrade, since it gives room to stretch out without pressing against the footboard.
Can a rolled UK king mattress fit up narrow stairs?
Rolling makes a big difference. The Komfi Serenity arrives vacuum packed and rolled, so you carry a compact roll rather than a flat 150 x 200cm mattress. Komfi doesn't publish a weight for the UK king, so plan on two people carrying it and check the retailer's details before buying.
What bedding fits a Komfi Serenity king size mattress?
Standard UK king sheets fit the 150 x 200cm surface, and a 230 x 220cm king duvet gives two people enough to share without tugging. The mattress is 20cm deep, so check that any fitted sheet you choose is made for that depth.