Harrison Spinks Diamond 25000 Pocket Single Mattress (Medium Feel)
The Harrison Spinks Diamond 25000 is a pocket spring mattress in a medium feel, which means it aims to balance cushioning with support rather than sitting at either extreme.
- Medium feel suits back & side sleepers
- Individually responsive springs
- From a long-established British maker
£2,049
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Harrison Spinks Diamond 25000 Pocket Mattress (Medium Feel)
More available sizes
Mattress details
Mattress
Harrison Spinks Diamond 25000 Pocket Mattress (Medium Feel)
Size
Firmness
Medium
Construction
Pocket Spring
Wool
Natural
Depth (cm)
Layers
6
Layer Details
Cortec Quad pocket springs
The core has 700 Cortec Quad springs, held in groups of four within a single fabric pocket, in a glue-free design. This gives the mattress its supportive base while each group can still respond to your body on its own.
Mini pocket springs
Layers of 24300 mini springs sit above the core and give more points of contact with your body. That means the surface can follow your shape more closely.
British wool comfort layers
Layers of British wool add snug, cushioned comfort over the springs. They soften the feel without relying on foam.
Wool, mohair and cashmere layer
A layer of wool, mohair and cashmere is added to enhance the indulgent feel. You should notice it as a softer, more cosseting surface.
Wool, hemp and flax layer
A blend of British wool, hemp and flax fibres increases durability within the comfort layers. The aim is to help the mattress keep its feel as it is used.
Cotton, hemp and flax layer
Additional layers of cotton, hemp and flax fibres wick away moisture. That should help the mattress feel drier and fresher through the night.
Layer details from harrisonspinks.co.uk and mattressonline.co.uk product pages, October 2026.
Key benefits
- Fits compact rooms: At 90cm wide, it leaves floor space free for a desk, wardrobe or toy storage in a child's room, or slides under the slope in a loft conversion.
- Pocket springs at one-person scale: Each spring responds to your body individually, which means proper contouring for a solo sleeper rather than the generalised support of a basic open-coil single.
- Guest rooms and dual-purpose spaces: A single keeps a spare room usable as an office during the day, and two singles suit hosting guests who'd rather not share.
- Cheap, easy bedding: Single sheets and duvets are the most widely stocked of any size, which keeps running costs down after a premium purchase.
- The lowest entry point to this model: The UK single is the smallest of the five sizes, so it's the least expensive route to Harrison Spinks pocket spring construction; compare the retailer prices shown on this page.
This size suits you if...
You're buying a long-lasting mattress for a child or teenager and want it to see them through to adulthood, you sleep alone in a compact room where every centimetre of floor space matters, or you're setting up a guest room and want visitors to sleep on something genuinely comfortable rather than an afterthought.
Consider another size if...
You're an adult who likes to stretch out, or two of you will ever share it. We'd recommend the UK double instead, which is 45cm wider than the UK single and the same length; allow at least 2.6m x 2.8m.
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FAQ's
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 for a UK single, which is our own guidance rather than the manufacturer's. That covers the 90 x 190cm mattress plus space to walk alongside and open drawers or doors. Most UK bedrooms, including small box rooms and lofts, clear this comfortably.
Is a UK single Diamond 25000 big enough for an adult?
For one adult, yes. At 90cm wide and 190cm long it's the standard UK one-person size, and the pocket springs support your body individually, so a solo sleeper isn't shortchanged on comfort. If you're tall or like to sprawl, the UK king is 60cm wider and 10cm longer, though it needs a room of at least 2.7m x 2.9m.
Should I choose the UK single or the UK small double?
The UK single is 30cm narrower than the UK small double, and the two are the same length. If the bed is for a child, a teenager or a compact spare room, the UK single is the sensible pick. A solo adult who wants extra rolling room would be happier on the UK small double, which needs a room of at least 2.4m x 2.8m.
Is the UK single a good size for a guest room?
Often, yes. A single keeps a spare room flexible, so it can double as an office or fit two beds with a walkway between them for guests who don't share. The medium feel is a safe middle ground for visitors with unknown preferences, though a couple staying regularly would need the UK double or larger.
Is the Diamond 25000 UK single worth it for a child's room?
It's a premium spend for a child's bed, and plenty of families would find a cheaper single perfectly adequate. The case for it is longevity: pocket spring support that can carry a child through their teens, backed by a 5 year guarantee at one listed retailer. If the mattress will be replaced in a few years anyway, spend less.