Harrison Spinks Diamond 25000 Pocket Single Mattress (Firmer Feel)
The Harrison Spinks Diamond 25000 is a firm pocket spring mattress whose springs move independently, so it responds to your shape and limits the ripple when a partner shifts.
- Firm feel for back & front sleepers
- Tends to sleep cooler than all-foam
- Supportive pocket sprung surface
£2,049
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Harrison Spinks Diamond 25000 Pocket Mattress (Firmer Feel)
More available sizes
Mattress details
Mattress
Harrison Spinks Diamond 25000 Pocket Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Natural
Depth (cm)
Layers
6
Layer Details
Wool and viscose
The top layers are a blend of British wool and viscose. This is the first thing you feel when you lie down, so it sets the soft, natural surface over the springs beneath.
Wool and mohair
A British wool and mohair blend sits below. It adds another natural layer of cushioning between you and the spring unit.
Cashmere
A cashmere layer comes next. It adds a soft natural fibre to the mix, so the surface feels less stark than a firm spring mattress might suggest.
Yorkshire wool, silk and British wool
This layer blends Yorkshire wool, silk and British wool. It continues the all-natural filling, adding to the comfort layers that sit over the springs.
Wool, hemp and flax
A British wool, hemp and flax blend that increases durability and breathability. For you, that means a filling that should hold up well over time and let air move through.
Cotton, hemp and flax
A cotton, hemp and flax blend that wicks away moisture. It helps keep the sleeping surface drier, which is useful if you sleep warm. Hemp and flax fibres are also hypoallergenic and antimicrobial.
Layer details from harrisonspinks.co.uk and mattressonline.co.uk product pages, October 2026.
Key benefits
- Fits compact rooms: At 3ft wide (3ft x 6ft 3in), the UK single leaves floor space free in box rooms, lofts and spare rooms that double as an office.
- Firm support for one: The catalogued firm feel suits back and front sleepers, and in a single you get that support without paying for width you will never use.
- Pocket springs, sized down: Independent pocket springs respond to your shape rather than pushing back as one flat surface, and the single carries the same construction as the larger sizes.
- Two singles beat one double for guests: In a guest room, a pair of UK singles gives visitors flexibility a shared bed cannot, and each still fits within our 2.1m x 2.8m guidance.
- Cheapest bedding of any size: Single sheets and a 135 x 200cm duvet are the most widely stocked and least expensive bedding you can buy.
This size suits you if...
You sleep alone, prefer a firm surface, and want premium pocket spring construction in the smallest, most affordable size this model comes in. It also suits a teenager moving up to a long-term mattress, or a spare room where the bed shares space with a desk and needs to stay out of the way.
Consider another size if...
You share the bed, or you sleep alone but like room to spread out. At 90cm wide the UK single is snug for a restless adult, so we'd recommend the UK double instead; it is 45cm wider, the same length, and we suggest at least 2.6m x 2.8m for it.
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FAQ's
What size is the Harrison Spinks Diamond 25000 UK single?
It measures 90 x 190cm, which is 3ft x 6ft 3in. That is the standard UK one-person size, so any UK single frame, standard single sheets and a 135 x 200cm single duvet will fit without alteration.
What room size do I need for the Diamond 25000 in a UK single?
We suggest allowing at least 2.1m x 2.8m of floor space. That is our own guidance rather than the manufacturer's, and it leaves enough room to walk round the bed and open drawers or a wardrobe. In a loft conversion, check the bed sits where you have full head height.
Is a UK single big enough for an adult?
For most solo adults, yes, though 90cm of width is snug if you move about a lot in the night. The firm feel helps here: a supportive surface keeps you settled rather than rolling toward an edge. If you regularly wake near the sides, consider the UK double, which is 45cm wider.
How much smaller is the UK single than the UK double?
The UK single is 45cm narrower than the UK double, and the two are the same length. That 45cm is the difference between a bedroom needing 2.1m x 2.8m of space and one needing at least 2.6m x 2.8m, which matters in smaller rooms.
Where can I buy the Diamond 25000 in a UK single?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them. Before ordering, confirm you are buying the firmer feel version in the UK single, as this model is sold in more than one firmness variant.