Sealy Duchess Contract Mattress
Mattress
Sealy Duchess Contract Mattress
Size
Firmness
Medium Firm
Construction
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.
- Real space for two: At 75cm each for two people sharing, you can turn over without negotiating, which matters when one of you gets up hours before the other.
- Length for taller sleepers: The UK king is 10cm longer than the UK double at 200cm, so anyone approaching six foot stops finding their feet at the edge.
- EdgeGuard across a wider bed: The reinforced border means the full 150cm width is usable sleeping space, helpful when a dog claims the middle as routine.
- Responsive springs, less disturbance: The PostureTech springs firm up under each sleeper's weight individually, which means one restless partner is felt a little less across the extra width.
- Turning is a two-person job at this size: This is a double-sided mattress that needs regular flipping, and at 5ft x 6ft 6in you'll want help doing it.
This size suits you if...
You share the bed every night and a double has started to feel like a compromise, one of you is tall enough that 190cm mattresses leave feet hanging, or your sleep schedules rarely line up and you want enough width that early alarms and late nights disturb each other less. Your room can take it too: we suggest at least 2.7m x 2.9m.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, especially once wardrobes are in. We'd recommend the UK double instead, which needs around 2.6m x 2.8m and is 15cm narrower.
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Is the Sealy Duchess Contract UK king big enough for two adults?
Comfortably. The 150 x 200cm surface gives 75cm each for two people sharing, and the EdgeGuard border keeps that width usable right to the sides rather than leaving a soft, sloping perimeter. If you currently share a double, the UK king is 15cm wider, a difference you notice every night rather than only on paper.
What room size do I need for a UK king mattress?
We suggest at least 2.7m x 2.9m for a UK king, and that's our guidance rather than Sealy's. New build master bedrooms can be tighter than they look once fitted wardrobes go in, so measure the clear floor space, then check you can still open doors and walk both sides of the bed.
Is the UK king long enough for someone over six foot?
It's the sensible choice. The UK king is 200cm long, 10cm longer than the UK double, so a sleeper around six foot gets clearance rather than toes brushing the footboard. If length is your only reason to size up, note the UK king and the UK super king are the same length, so width is the only remaining question.
Is the Sealy Duchess Contract hard to turn in a UK king?
It takes two people. This is a double-sided design that needs regular flipping to wear evenly, and at 5ft x 6ft 6in it's an awkward shape for one person to manage safely. If you live alone or have a bad back, factor that into the size decision before you buy.
Should I get the Sealy Duchess Contract in a UK king or a UK super king?
The UK king is 30cm narrower than the UK super king, and both are 200cm long. For most couples the UK king is the sweet spot: enough width to sleep without disturbing each other, without needing the 3m x 2.9m we suggest for the UK super king. Size up if a pet or child regularly joins you.