Harrison Spinks Diamond 25000 Pocket 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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The Harrison Spinks Diamond 25000 uses pocket springs that move independently, so you should feel less disturbance when a partner shifts during the night. It sits firmly at the premium end of the market. It comes in five UK sizes, from Single up to Super King. Only basic details are available for this model, so its layer-by-layer construction can't be confirmed, and it's a significant spend to make on limited information.
Mattress specifications
Firmness
Medium
Type
Pocket Spring
Depth (cm)
Number of Layers
6
Trial Period (nights)
Warranty (years)
Price Range
£2,049 to £3,929
Best Sleeping Position(s)
Side Sleeping
Back Sleeping
Combination Sleeping
Certifications
Assessed from the product page published by Mattress Online, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
A medium feel tends to suit the widest range of sleepers, particularly back sleepers and side sleepers who want some give at the shoulder and hip. Pocket spring construction means each spring responds to your body individually, which usually translates to better spinal alignment than a basic open-coil design. Yes, the starting price is high, but Harrison Spinks is a long-established British manufacturer, and this model is listed with a 5 Year Guarantee. If you're weighing this against cheaper foam options, the appeal here is a traditional sprung feel with independent support, though we'd suggest confirming the full specification with the retailer before committing.
Key features & 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.
Best suited for?
Couples
Pocket springs that move independently mean you should feel less disturbance when your partner shifts during the night, so each of you can settle more easily.
Side sleepers
The medium feel gives some give at the shoulder and hip, which suits anyone who sleeps on their side and wants the mattress to ease around them.
Back sleepers
Each pocket spring responds to your body individually, which usually means more even support along the back than a basic open-coil design would give.
Combination sleepers
A medium feel suits the widest range of sleepers, so it works as a middle-ground choice if you change position through the night.
If your budget is below the starting price, this is out of reach in any size. Sleepers who firmly prefer a very soft or very firm surface may find this Medium variant a compromise. And if you want full construction detail before buying, the limited published specification may put you off.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Harrison Spinks Diamond 25000 Pocket Mattress (Medium Feel)
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FAQ's
How firm is the harrison spinks diamond 25000 mattress?
This entry covers the Medium feel version, a middle-of-the-road tension that suits most back and side sleepers. Be aware the retailer's page offers the Diamond 25000 in more than one firmness option, so check you're selecting Medium at checkout if that's the feel you want.
What sizes does the harrison spinks diamond 25000 come in?
Five UK sizes are listed: Single, Small Double, Double, King and Super King.
Does the harrison spinks diamond 25000 have a guarantee?
The retailer listing for this mattress states a 5 Year Guarantee. That figure comes from the retailer rather than a Harrison Spinks brand page, so it's sensible to confirm the guarantee terms directly with wherever you buy.
How much does the harrison spinks diamond 25000 cost?
It depends on the size you choose, and the price table on this page shows the current price for each size. It sits at the premium end of the pocket spring market, so it's a considered purchase rather than a budget buy.
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