Last seen for £1,092.25 at Mattress Man on 10th November 2026
Silentnight UltraGel 3000 Pocket Boxtop Medium Firm King Size Mattress
The Silentnight UltraGel 3000 Pocket Boxtop is a medium firm hybrid, pairing pocket springs with gel comfort material and a boxtop finish, which means you get support underneath with a plumper, more cushioned sleeping surface than a standard flat-top mattress.
- Medium-firm feel suits most sleepers
- Box top softens the first feel
- From a long-established UK name
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 £905.25 at Mattress Man on 27th October 2026
Last seen for £1,092.25 at Mattress Man on 10th November 2026
Last seen for £1,321.75 at Mattress Man on 10th November 2026
Last seen for £905.25 at Mattress Man on 10th November 2026
Last seen for £733.50 at Mattress Man on 27th October 2026
Mattress details
Mattress
Silentnight UltraGel 3000 Pocket Boxtop Medium Firm Mattress
Size
Firmness
Medium Firm
Construction
Pocket Spring
Hybrid
Gel
Depth (cm)
Layers
Layer Details
Key benefits
- More room each: You get 75cm of width per sleeper, which is 7.5cm more each than a UK double and enough that elbows and knees stop meeting in the night.
- Extra length for tall sleepers: At 200cm long, the UK king is 10cm longer than a UK double, so anyone around six foot can lie flat without their feet hanging off the end.
- Fewer disturbances from a partner: The wider surface puts a little more distance between you, which helps if one of you rises well before dawn and the other needs another two hours.
- Space for the family dog: If a dog sleeps on the bed every night, the 15cm of extra width over a UK double gives it somewhere to curl up without pushing you towards the edge.
- Cushioned top across a bigger surface: The boxtop gives a plumper, softer first feel over the supportive pocket springs, and in a UK king there's more of that surface for each of you to settle into.
- Fits more rooms than a super king: We suggest allowing at least 2.7m x 2.9m for a UK king, which is less floor space than the UK super king needs.
This size suits you if...
You share the bed every night and a UK double has started to feel cramped, one of you is close to six foot and wants proper length, or your working hours differ and you'd like more distance from a partner getting up in the dark.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m once wardrobes are in. We'd recommend the UK double instead, for which we suggest at least 2.6m x 2.8m.
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FAQ's
Is the Silentnight UltraGel 3000 UK king big enough for two adults?
For most couples, yes. The UK king gives 75cm each for two people sharing, which is 7.5cm more each than a UK double. If you both sprawl or one of you shifts about a lot, the UK super king gives 90cm each, so sizing up would give you 15cm more per person.
Is a UK king UltraGel 3000 long enough if you're over 6ft?
The UK king is 200cm long, or 6ft 6in, which is 10cm longer than a UK double. That extra length is often the real reason tall sleepers upgrade. If you're comfortably over six foot, you'll lie flat with more room at your feet than a UK double would allow.
UltraGel 3000 UK king or UK super king for a couple?
The UK king and the UK super king are the same length, so the choice comes down to width and your room. The UK super king gives 90cm each against 75cm in the UK king. We suggest at least 3m x 2.9m for the UK super king, and at least 2.7m x 2.9m for the UK king.
Will a king size mattress stop my partner waking me up?
A UK king gives you more space than a UK double, 7.5cm more each, so there's a little more gap between you when one person turns over or gets up early. It won't remove disturbance entirely. If one of you keeps very different hours, the extra space in a UK super king may suit you better.
How much floor space do I need for a Silentnight UltraGel 3000 in a UK king?
We suggest allowing at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable once bedside tables are on both sides. New build master bedrooms can be tighter than they look after fitted wardrobes go in, so measure the clear floor, not the whole room.