Sealy PostureLux Forbes King Size Mattress
The Sealy PostureLux Forbes Mattress combines a latex comfort layer with PostureTech pocket springs and UniKey edge support, which means a buoyant, medium-feel surface with a stable edge to sit or sleep on.
- Buoyant latex pressure relief
- Springs adapt to your body shape
- Stable UniKey edge support
£1,799
Get the lowest price we've found
Save with the previous model
Some retailers still sell the earlier version of this mattress for less than the current model's best price.
Sealy PostureLux Forbes Mattress
More available sizes
Mattress details
Mattress
Sealy PostureLux Forbes Mattress
Size
Firmness
Medium
Construction
Foam
Latex
Pocket Spring
Depth (cm)
32
Layers
3
Layer Details
Latex comfort layer
A latex layer that delivers pressure relief and a naturally buoyant feel. You sit on the surface rather than sinking deep into it.
Sealy medium premium foam
A double layer of Sealy's medium premium foam, creating a complete comfort stack. It adds cushioning beneath the latex to keep the medium feel consistent.
PostureTech Core Support Plus springs
Springs with six turns each, twice tempered, with UniKey edge support. They adapt to your body shape and keep the edges steadier when you sit or sleep near them.
Layer details from crushedvelvetbedstore.co.uk product page, November 2026.
Key benefits
- More room each: Moving up from a UK double gives you 7.5cm more each, which means fewer elbows and knees meeting when one of you turns over in the night.
- Length for taller partners: At 200cm, the UK king is 10cm longer than the UK double, so a partner over six foot is less likely to end up with their feet hanging off the end.
- Edges you can use: UniKey edge support helps the sides hold up when you sit or lie near them, so each of you can use your full 75cm right out to the edge.
- A little more distance from an early riser: The PostureTech springs adapt to each body, and the extra UK king width puts slightly more space between a partner leaving at dawn and one still asleep.
- Room for pillows and propping: During pregnancy or recovery, the UK king leaves space for a support pillow or a shifted position without pushing your partner towards the edge.
This size suits you if...
You share the bed every night and have outgrown a UK double, one of you is close to or over six foot, or your schedules differ and you'd like a little more distance when one of you gets up hours before the other.
Consider another size if...
Your bedroom is smaller than 2.7m x 2.9m once wardrobes and bedside tables are in. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
Similar Mattresses in This Price Range
Did you know? On Mattress Unboxed we have over 1,000 different mattresses to suit all types of sleepers. View all mattresses.
FAQ's
Is the Sealy PostureLux Forbes UK king big enough for two people?
For most couples, yes. A UK king gives you 75cm each, which is 7.5cm more each than a UK double. If one of you sprawls, or a dog regularly joins you, the UK super king gives 90cm each, although it needs a noticeably bigger room.
Sealy PostureLux Forbes UK king vs super king: which should couples choose?
The UK super king is 30cm wider and the same length, so the UK king gives you 15cm less each. We suggest at least 3m x 2.9m for the UK super king against at least 2.7m x 2.9m for the UK king. If your room is tight, the UK king is the more practical choice.
What room size do I need for a UK king Sealy PostureLux Forbes?
Allow at least 2.7m x 2.9m, with 3.2m x 3.2m being comfortable. Measure after wardrobes go in, as new build master bedrooms often feel smaller once they're furnished. Leave enough clearance on both sides so each of you can get in and out without squeezing past furniture.
Is the UK king Sealy PostureLux Forbes long enough for someone over 6ft?
At 200cm, or 6ft 6in, the UK king is 10cm longer than the UK double. The UK super king is the same length, so if length is your main concern rather than width, the UK king gives you the extra legroom without needing the bigger room.
What size duvet and sheets fit a Sealy PostureLux Forbes king size?
Standard UK king sheets and a 230 x 220cm king duvet fit. The mattress is 32cm deep, so check that your fitted sheet has deep enough pockets before you buy, then compare the retailers listed on this page.