Sealy Duchess Contract Single Mattress
The Sealy Duchess Contract is a medium firm sprung mattress with a quilted surface, available in UK Single, Double, King and Super King sizes.
- Suits most back & combination sleepers
- Usable space right to the edges
- 5-year guarantee
£599
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Sealy Duchess Contract Mattress
More available sizes
Mattress details
Mattress
Sealy Duchess Contract Mattress
Size
Firmness
Medium Firm
Construction
Foam
Depth (cm)
26
Layers
4
Layer Details
Quilted Surface
A quilted sleep surface sits on top, which means a soft, slightly cushioned first impression when you lie down. It's a traditional finish rather than a plush pillow-top feel.
Sealy Medium Foam
Generous layers of Sealy medium foam add comfort between you and the springs. This is what softens the medium firm support so it doesn't feel hard at the surface.
PostureTech Core Support Springs
The PostureTech Core Support system uses springs that gradually get firmer as pressure increases, which means heavier areas like your hips get deeper support while lighter areas rest more gently. The result is pressure relief without sagging.
EdgeGuard
EdgeGuard reinforces the perimeter for added durability and edge-to-edge support. In practice, that gives you more usable sleeping space right up to the sides.
Layer details from sealy.co.uk product page, September 2026.
Key benefits
- A compact footprint that leaves room to live: At 90cm wide, this size fits a child's bedroom alongside a desk, wardrobe and toy storage without swallowing the floor.
- EdgeGuard matters more in a narrow bed: The reinforced border gives usable support right to the sides, which counts when the whole bed is only 3ft wide to begin with.
- The easiest size to turn: This is a double-sided mattress that needs regular flipping, and the UK single is the one size most people can manage alone.
- Support that grows with a teenager: The PostureTech springs firm up gradually under pressure, so the same mattress keeps supporting a child properly as they get taller and heavier.
- Pairs neatly in a shared or guest room: Two UK singles plus a walkway fit where one big bed won't, handy for siblings sharing or a guest room set up for visitors.
- Cheap, easy bedding: Standard single sheets and a 135 x 200cm single duvet fit, the most widely stocked and affordable bedding of any UK size.
This size suits you if...
You're buying for a child or teenager and want a supportive sprung mattress rather than a cheap foam slab, you sleep alone in a compact room, or you're furnishing a guest room or spare-room office where a single leaves space for a desk. It also suits a student room or first flat where the frame is provided and the mattress isn't.
Consider another size if...
You're an adult who shares the bed, or you simply want more room to spread out than 90cm allows. We'd recommend the UK double instead, which is 45cm wider and the same length; allow at least 2.6m x 2.8m of floor space.
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FAQ's
Is the Sealy Duchess Contract UK single big enough for an adult?
For most adults sleeping alone, yes. At 90 x 190cm it's the standard UK one-person size, and the EdgeGuard border means you can use the full width without feeling like you'll roll off. Taller sleepers should note it's 190cm long; the UK king version of this mattress is 10cm longer if that's a concern.
What room size do I need for the Sealy Duchess Contract single?
We suggest at least 2.1m x 2.8m of floor space, which gives you room to walk around the bed and open drawers or a wardrobe. That's our guidance rather than Sealy's, and it makes the UK single a realistic fit for box rooms, loft conversions with a narrow footprint, and spare rooms doubling as an office.
Can I use the Sealy Duchess Contract single on a bunk or mid sleeper frame?
The 90 x 190cm footprint matches standard UK bunk and mid sleeper frames, so the size itself fits. Raised frames often have a maximum mattress depth for safety rails, though, so check your frame's limit against the depth Sealy publishes for this mattress before you buy.
Is the UK single hard to turn regularly?
It's the easiest size of this mattress to manage. The Duchess Contract is double-sided and needs turning to wear evenly, which is a chore in the bigger sizes, but a UK single is narrow enough that one adult can usually flip it without help. Worth remembering if you're buying for an elderly relative or a child's room.
How much smaller is the UK single than the UK double?
The UK single is 45cm narrower than the UK double, and both are the same 190cm length. If two of you will share the bed, or a teenager wants more sprawl room, the UK double is the sensible step up; allow at least 2.6m x 2.8m of floor space for it. Compare prices for both in the retailer table on this page.