Rest Assured Adleborough 1400 Pocket Ortho King Size Mattress
The Rest Assured Adleborough 1400 is a pocket spring mattress with an extra firm feel, handcrafted in the UK.
- Genuinely extra-firm support
- Fibre top softens the surface
- Minimises partner disturbance
£625
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Rest Assured Adleborough 1400 Pocket Ortho Mattress
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Mattress details
Mattress
Rest Assured Adleborough 1400 Pocket Ortho Mattress
Size
Firmness
Extra Firm
Construction
Pocket Spring
Orthopaedic
Depth (cm)
26
Layers
2
Layer Details
Comfort Layer
Soft white fibre fillings sit at the surface, which means the extra firm springs beneath don't feel harsh against your body. It's a cosy top rather than a plush one, so expect comfort without much sink.
Support System
1400 individual pocket springs, each encased in its own cloth pocket, adapt to your movement and distribute support to each part of your body. This gives firmer, more localised support than an open coil design, and less disturbance from a partner moving about.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- More room each: At 75cm per sleeper, you each gain 7.5cm over a UK double, which means fewer elbows in the night and a little more space to turn over.
- Length for taller sleepers: The UK king is 10cm longer than the UK double, so a partner over six foot can stretch out without their feet hanging off the end.
- Less disturbance across a wider bed: Individually pocketed springs respond to each of you separately, and the extra width puts more distance between you when one partner gets up early.
- Firm edges for getting up: The extra firm feel stays solid as you shift towards the side of a UK king, which helps anyone who needs steady footing when getting out of bed.
- Fits a typical master bedroom: We suggest at least 2.7m x 2.9m for the UK king, a smaller room than we suggest for the UK super king.
This size suits you if...
You share the bed and keep waking when your partner turns over or gets up, one of you is approaching or over six foot and a UK double feels short, and you both like a genuinely firm mattress with pocket springs rather than a soft, sinking one.
Consider another size if...
You need the most separation possible, such as with very different schedules or a dog that sleeps between you. We'd recommend the UK super king instead, which gives 90cm each; allow at least 3m x 2.9m.
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FAQ's
Is the Adleborough 1400 UK king big enough for two adults?
For most couples, yes. The UK king gives you 75cm each, which is 7.5cm more per person than a UK double. If you both sprawl, or a pet sleeps on the bed every night, the UK super king gives 90cm each and may suit you better.
Will a UK king Adleborough 1400 suit a tall partner?
It should help. At 200cm long (6ft 6in), the UK king is 10cm longer than the UK double, so a partner around or over six foot has more room before their feet reach the end. The UK super king is the same length, so going wider there adds no extra length.
Does a firm king size mattress reduce partner disturbance?
The pocket springs in the Adleborough 1400 move individually, so one partner turning over causes less movement on the other side. The UK king also puts a little more distance between you than a UK double, which helps if one of you rises hours before the other.
Adleborough 1400 king or super king for a new build bedroom?
New build master bedrooms often feel smaller once wardrobes are fitted. We suggest at least 2.7m x 2.9m for the UK king and at least 3m x 2.9m for the UK super king, so measure the floor space left after furniture before you choose.
Is the extra firm Adleborough 1400 king good during pregnancy?
The UK king's extra width leaves room for support pillows without crowding your partner. The extra firm feel may be too firm if you are side sleeping for months, though, since there is only a modest fibre top and no memory foam, so consider how you sleep before committing.