Sealy PostureTech Oxwich Mattress
The Sealy PostureTech Oxwich Mattress pairs twice-tempered PostureTech springs with a thin polyester fibre layer, which means you get firm, responsive support with only a light cushion on top.
- Extra-firm feel for back sleepers
- Responsive support at pressure points
- Reinforced edges against roll-off
£299
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The Sealy PostureTech Oxwich is a handmade-in-the-UK spring mattress, 24cm deep, with a polyester fibre layer under a tufted damask cover. It's rated extra firm, so it suits sleepers who want a flat, unyielding surface, particularly on their back or front. It comes in a UK single, UK double, UK king and UK super king. Dreams offers a 100-night trial, and a 5-year guarantee applies.
Mattress specifications
Firmness
Extra Firm
Type
Depth (cm)
24
Number of Layers
2
Trial Period (nights)
Warranty (years)
Price Range
£299 to £599
Best Sleeping Position(s)
Stomach Sleeping
Certifications
Assessed from the specification published by crushedvelvetbedstore.co.uk, captured November 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
The Oxwich is built around firm support. Twice-tempered PostureTech springs give a responsive base, and Sealy says they support pressure points, so your body stays on top of the mattress rather than sinking in. EdgeGuard reinforcement sits inside the spring unit to help against roll-off, which makes the edges more usable for sitting or sleeping near the side. Traditional tufting holds the fillings in place. It's also double-sided, so turning and rotating it regularly helps it wear evenly. It suits back and front sleepers who want a firm feel, although the cushioning is light.
Key features & layer details
Polyester fibre layer
Super soft polyester fibres sit over the spring unit under a traditionally tufted damask cover. They add a light cushion to your movement, though the surface still feels firm.
PostureTech Core Support spring unit
Twice-tempered PostureTech springs form the foundation and give maximum support to pressure points, with EdgeGuard tucked inside. You get firm, responsive support and a reinforced edge against roll-off.
Layer details from crushedvelvetbedstore.co.uk product page, November 2026.
Best suited for?
Back sleepers
The extra firm rating and twice-tempered PostureTech springs give a flat, unyielding surface, so your body stays on top of the mattress rather than sinking in.
Front sleepers
A firm feel with only a thin polyester fibre layer over the springs keeps the surface flat, which suits anyone who wants to lie face down without sinking.
Couples
EdgeGuard reinforcement inside the spring unit helps against roll-off, so both people can sit or sleep near the side of the bed without feeling unsupported.
Combination sleepers
Responsive springs and a double-sided build let you shift position easily, and turning the mattress regularly helps it wear evenly over time.
If you prefer sleeping on a soft or medium mattress, this might not be the best choice. It's rated extra firm and has only a thin polyester fibre layer over the springs, so there's little give for shoulders and hips. Side sleepers and lighter sleepers may find it too hard. Sealy doesn't publish a spring count for it.
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.
Sealy PostureTech Oxwich Mattress
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FAQ's
How firm is the Sealy PostureTech Oxwich Mattress?
It's rated extra firm, which gives a flat, unyielding surface with little sink. That suits sleepers who want firm support, although side sleepers and anyone who likes a softer feel may find it too hard.
What sizes does the Sealy PostureTech Oxwich Mattress come in?
It comes in a UK single, UK double, UK king and UK super king. Check your bed frame size against those four before choosing, as other sizes aren't stated.
How deep is the Sealy PostureTech Oxwich Mattress?
It's 24cm deep. That should sit comfortably on most standard bed frames, though with only a thin polyester fibre layer over the springs, the depth comes mainly from the spring unit rather than thick cushioning.
Do you need to turn the Sealy PostureTech Oxwich Mattress?
Yes. It's double-sided, so you should turn and rotate it regularly. This spreads wear across both sides and helps it keep its shape, and the traditional tufting holds the fillings in place.
Does the Sealy PostureTech Oxwich Mattress come with a trial or guarantee?
Dreams offers a 100-night trial, which is the retailer's own offer. A 5-year guarantee applies too. Terms can vary by retailer, so check the details before you buy.
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