Sealy Ortho Plus Gold Mattress
The Sealy Ortho Plus Gold is a firm, double-sided mattress built around Sealy's PostureTech CS springs, which respond to your body weight to give deeper support where you carry the most pressure.
- Extra lumbar support at the centre
- Firm edges, no roll-off feeling
- Double-sided for a longer life
£389
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At 29cm deep, the Sealy Ortho Plus Gold is hand-tufted and turnable, which means you can flip it to even out wear over the years. It comes in five sizes from UK Single to Super King. It's made by an NBF-Approved Manufacturer and comes with a Sealy 5 year guarantee, as stated on the MattressNextDay listing. If you want a traditional firm sprung mattress rather than memory foam, this is very much that.
Mattress specifications
Firmness
Firm
Type
Open Coil Spring
Depth (cm)
29
Number of Layers
3
Trial Period (nights)
Warranty (years)
5
Price Range
£389 to £679
Best Sleeping Position(s)
Back Sleeping
Stomach Sleeping
Certifications
BS 7177
Assessed from the specification published by MattressNextDay, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
The main draw here is proper firm support at a sensible price. The PostureTech CS springs are twice tempered, which means they've been heat-treated twice to hold their shape for longer, and the listing describes a PowerPack in the centre of the mattress for extra lumbar support. EdgeGuard, a high-density foam strip lining the springs, firms up the edges so you can sit or sleep near the side without that roll-off feeling. Being double-sided is rarer these days, and it genuinely extends the life of a mattress if you're willing to turn it. Yes, the fillings are polyester rather than natural fibres, but polyester recovers well and keeps the price down.
Key features & layer details
Cover
A breathable Belgian damask fabric cover, which means air can move through the sleep surface rather than getting trapped. That helps if you tend to run warm at night.
Comfort Fillings
100% polyester fillings that offer good recovery and durability. In practice that means the comfort layer springs back into shape rather than developing body impressions quickly.
Support System
PostureTech CS springs respond to your body weight, targeting key areas to give deep-down support where you need it most. The springs are twice tempered, a heat treatment that helps them keep their tension over time.
Layer details from mattressnextday.co.uk product page, September 2026.
Best suited for?
Back sleepers
The firm PostureTech CS springs and central PowerPack give a flat, supportive surface, which suits anyone who likes to lie on their back.
Front sleepers
Firm support from the twice tempered springs keeps the middle of the body from sinking in, which is what front sleepers usually want.
Warm sleepers
A breathable Belgian damask cover lets air move through the sleep surface instead of trapping it, so the bed feels less stuffy at night.
Couples
EdgeGuard foam firms up the edges, so you can sleep or sit near the side without that roll-off feeling, leaving more usable space.
Heavier sleepers
Springs that respond to body weight and twice tempered steel help hold their tension over time, so the mattress keeps its firm feel.
This is a firm mattress, so lightweight side sleepers may find it a little too unyielding on the shoulders and hips. If you prefer the slow, cradling feel of memory foam, a traditional sprung mattress like this won't give you that. And if you'd rather never flip a mattress, its double-sided design loses some of its point.
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 Ortho Plus Gold Mattress
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FAQ's
Is the Sealy Ortho Plus Gold mattress firm?
Yes, Sealy rates it as firm. The PostureTech CS springs give deep-down support that responds to your body weight, and the listing describes a central PowerPack for added lumbar support. It suits back and front sleepers best, although lightweight side sleepers may find it slightly too firm.
Can you flip the Sealy Ortho Plus Gold mattress?
Yes, it's a double-sided, turnable design, which is increasingly uncommon. Flipping it regularly helps the fillings wear evenly, so it should stay comfortable for longer than a one-sided equivalent. It's also hand-tufted, which holds the fillings in place.
How deep is the Sealy Ortho Plus Gold mattress?
It's 29cm deep, so standard fitted sheets should fit without trouble. The height comes from polyester comfort fillings and soft white fibres over the PostureTech CS spring support system, all wrapped in a Belgian damask cover.
What guarantee does the Sealy Ortho Plus Gold come with?
The MattressNextDay listing states a Sealy 5 year guarantee. No sleep trial is mentioned on the page, so check returns terms with your retailer before you buy. MattressNextDay also lists free next day delivery to mainland UK, though some addresses may incur a small fee.
What sizes does the Sealy Ortho Plus Gold come in?
Five UK sizes: Single, Small Double, Double, King and Super King. The price is reasonable for a hand-tufted, double-sided sprung mattress from an NBF-Approved Manufacturer.
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