Last seen for £488.58 at Archers Sleepcentre on 8th September 2026
Silentnight Just Sleep Bliss Gel Mirapocket 1000 King Size Mattress in a Box
The Silentnight Just Sleep Bliss Gel Mirapocket 1000 is a rolled mattress that arrives compressed in a box, which means it's easier to get up stairs and into the bedroom than a traditional flat delivery.
- Gentle medium-soft feel
- Zoned support for spinal alignment
- Hypoallergenic soft-knit surface
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 £358.10 at Archers Sleepcentre on 8th September 2026
Last seen for £488.58 at Archers Sleepcentre on 8th September 2026
Last seen for £443.38 at Archers Sleepcentre on 8th September 2026
Mattress details
Mattress
Silentnight Just Sleep Bliss Gel Mirapocket 1000 Mattress in a Box
Size
Firmness
Medium Soft
Construction
Pocket Spring
Rolled
Gel
Depth (cm)
Layers
2
Layer Details
Gel-infused comfort layer
A gel-infused comfort layer at the top of the mattress. For you, that means a soft, comfortable surface to settle into at night.
Mirapocket spring unit
1000 Mirapocket springs that respond independently to your body's movements, with zoned support. This means the springs adjust to each part of your body, which Silentnight says improves spinal alignment.
Layer details from marksandspencer.com product page, October 2026.
Key benefits
- 75cm each for two sharing: Two people get 75cm of width apiece, which means fewer accidental elbows and less waking each other when one of you turns over.
- Extra length for taller sleepers: At 200cm long, the UK king gives anyone approaching 6ft an extra 10cm over the UK double, so feet stay on the mattress rather than off the end.
- Boxed delivery suits king-sized rooms: A 150cm-wide mattress delivered flat is a struggle on a landing, so the rolled, boxed format makes this size genuinely easier to get upstairs.
- The biggest size in this range: This model comes in UK single, UK double and UK king only, so the UK king is your pick if space matters most.
- Room to shift positions: The extra width helps if one of you props pillows, changes position through the night or shares the bed with a dog that takes more than its share.
This size suits you if...
You share the bed every night and a double has started to feel cramped, if one of you gets up hours before the other and the movement wakes them, or if either partner is approaching 6ft and wants their feet to stay on the mattress. Allow at least 2.7m x 2.9m of floor space, with 3.2m x 3.2m feeling comfortable.
Consider another size if...
Your bedroom falls under our suggested 2.7m x 2.9m minimum, or you sleep alone. We'd recommend the UK double instead, which is 15cm narrower and needs at least 2.6m x 2.8m of floor space.
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FAQ's
Is the UK king Bliss Gel Mirapocket 1000 big enough for two adults?
Yes, comfortably for most couples. At 150cm wide you each get 75cm of space, which is where partner disturbance really starts to drop. If one of you is regularly up in the night, or you're propping pillows through pregnancy, that extra room makes shifting position far less disruptive.
How much bigger is the UK king than the double in this mattress?
The UK king is 15cm wider and 10cm longer than the UK double. The width is what you feel night to night as a couple, while the length matters most if either of you is tall. Silentnight sells this model in both sizes, so the choice usually comes down to room space.
Will a UK king fit in a new build master bedroom?
Often, but measure first. New build masters can feel smaller than they look once wardrobes are in. We suggest at least 2.7m x 2.9m for a UK king, with 3.2m x 3.2m feeling comfortable. If your room falls short, the UK double needs at least 2.6m x 2.8m.
Does the Silentnight Bliss Gel Mirapocket 1000 come in a super king?
No. The UK king is the largest size available in this model, alongside the UK single and UK double. If you have your heart set on a super king, which is 30cm wider than the UK king and the same length, you'd need to look at a different mattress.
Is the king size version good for a tall sleeper?
Length is the quiet benefit here. The UK king is 200cm long, or 5ft x 6ft 6in in imperial terms, which gives someone over 6ft an extra 10cm compared with the UK double. For a tall sleeper, that added length is often the real upgrade rather than the width.