Last seen for £725.61 at Archers Sleepcentre on 26th October 2026
Silentnight Just Sleep Calm Mirapocket 1000 King Size Mattress in a Box
The Silentnight Just Sleep Calm Mirapocket 1000 is a mattress in a box from one of the UK's best known sleep brands, delivered rolled and compressed so you can carry it to the bedroom before it expands.
- Boxed for easy carrying upstairs
- Fits most UK bed frames
- From a long-established British maker
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 £725.61 at Archers Sleepcentre on 26th October 2026
Last seen for £651.26 at Archers Sleepcentre on 26th October 2026
Last seen for £829.63 at Archers Sleepcentre on 26th October 2026
Last seen for £494.42 at Archers Sleepcentre on 26th October 2026
Mattress details
Mattress
Silentnight Just Sleep Calm Mirapocket 1000 Mattress in a Box
Size
Firmness
Medium
Construction
Pocket Spring
Rolled
Depth (cm)
Layers
Layer Details
Key benefits
- Proper space for two: At 75cm each for two people sharing, you can turn over or stretch out without negotiating for territory.
- Length for taller sleepers: The UK king is 10cm longer than the UK Double, which matters more than width if one of you is approaching six foot.
- Less partner disturbance: If one of you gets up hours before the other, the wider surface means an early alarm is less likely to shake the whole bed.
- Boxed delivery suits bigger sizes: A king is an awkward thing to move flat, so the rolled, compressed format makes stairs and doorways far less of a battle.
- Easy bedding to buy: Standard king sheets and a 230 x 220cm king duvet fit, both stocked almost everywhere in the UK.
This size suits you if...
You share the bed every night and the double has started to feel like a compromise, especially if one of you keeps different hours or is a restless sleeper. It also suits couples where one partner is tall, since the 200cm length adds breathing room at the foot of the bed, and anyone whose dog has quietly claimed a permanent spot on the duvet.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest for a UK king. In that case the UK double of this mattress would suit you better, and we suggest at least 2.6m x 2.8m for that size.
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FAQ's
How big is the Silentnight Calm Mirapocket 1000 in a UK king?
It measures 150 x 200cm, or 5ft x 6ft 6in. For two people sharing, that gives 75cm of width each, which is where a king earns its reputation as the standard upgrade for couples who find a double a little tight.
Will the king size Calm Mirapocket 1000 fit my bedroom?
We suggest a room of at least 2.7m x 2.9m for a UK king, which leaves space to walk round the bed and open drawers. New build master bedrooms can be deceptive: measure with the wardrobes in place, not the empty floor plan.
Is a UK king worth it over a double for this mattress?
The UK king is 15cm wider and 10cm longer than the UK Double. The width is what you notice night to night, though for taller sleepers the extra length is often the real reason to size up. If your room can take it, most couples don't regret the move.
Should I choose the king or super king Calm Mirapocket 1000?
The UK king is 30cm narrower than the UK Super King, and both are the same 200cm length. If your room meets the 3m x 2.9m we suggest for a UK super king and you want maximum space, size up. Otherwise the UK king is the more practical fit.
How does the boxed delivery work for a king size mattress?
The mattress arrives rolled and compressed, so a size that would be unwieldy flat can be carried upstairs by one or two people before it expands. That's a genuine advantage at king size, where a conventional flat delivery often struggles on landings and tight turns.