Mattress Online Classic Gold Ortho King Size Mattress
The Classic Gold Ortho is Mattress Online's entry-level orthopaedic model, built around traditional open coil springs with a soft fibre comfort layer on top.
- Helps keep your spine aligned
- Breathable cover for warm sleepers
- 100-night trial
£248
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Mattress Online Classic Gold Ortho Mattress
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Mattress details
Mattress
Mattress Online Classic Gold Ortho Mattress
Size
Firmness
Medium Firm
Construction
Orthopaedic
Open Coil Spring
Depth (cm)
26
Layers
3
Layer Details
Comfort Layer
Soft white synthetic fibres sit at the top, which means a cosy initial feel rather than a firm, flat surface. They're durable and resilient, designed to hold their shape over time.
Support System
Traditional open coil springs are interlaced and joined in a lattice design, which means your weight is distributed evenly across the bed. That helps relieve built-up pressure and supports spinal alignment, the core job of an orthopaedic mattress.
Cover
A knitted cover gives a soft, warm finish. It also enhances airflow and is breathable, which helps if you run a little hot at night.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Real space for two: At 75cm each for two sharing, you get 7.5cm more per person than the UK double, enough to change position without negotiating.
- Extra length for taller sleepers: The UK king is 200cm long, 10cm more than the UK double, so anyone approaching six foot stops finding the footboard with their toes.
- Distance softens the motion transfer: Open coils do pass on more movement than pocket springs, but the wider UK king puts more mattress between you, which takes the edge off a restless partner.
- Budget mattress, upgrade size: Because the Classic Gold Ortho sits at the entry level, sizing up to a UK king costs less than it would on most orthopaedic models.
- Firm support across the full width: The interlaced lattice of springs spreads weight evenly right across the 150cm, so the extra space is properly supported rather than soft at the edges.
This size suits you if...
You share the bed every night and a double has started to feel tight, especially if one of you is on the taller side and wants the 200cm length. It also makes sense if you keep different hours, one up early while the other sleeps on, and want enough width that getting in and out disturbs the other less.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest as a minimum for a UK king. In that case the UK double would suit you better, and it only needs a room of around 2.6m x 2.8m.
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FAQ's
Is the Classic Gold Ortho UK king good for couples?
Yes, with one caveat. The 150cm width gives 75cm each for two sharing, and the medium firm open coil support runs evenly across the whole surface. Open coils do transfer more movement than pocket springs, though, so the extra width of the UK king matters here: it puts more distance between you and a fidgety partner.
What room size do I need for the Classic Gold Ortho in a UK king?
We suggest at least 2.7m x 2.9m, with something closer to 3.2m x 3.2m feeling comfortable. New build master bedrooms can be deceptive: once fitted wardrobes and bedside tables go in, a room that looked generous on the plan can leave narrow walkways, so measure the usable floor rather than the wall to wall figure.
Should I get the Classic Gold Ortho in a UK king or a UK double?
If one of you is close to six foot, the UK king. It's 10cm longer than the UK double as well as 15cm wider, and length is the difference tall sleepers actually feel. If your room is under our 2.7m x 2.9m suggested minimum, the UK double is the sensible compromise, needing around 2.6m x 2.8m.
How big is the UK king Classic Gold Ortho in feet?
It measures 5ft x 6ft 6in, which is 150 x 200cm in metric. That makes it 15cm wider and 10cm longer than a UK double, so check both dimensions against your room and your stairs before ordering, since a king mattress is a noticeably bigger object to manoeuvre.
Is the UK king worth it if the dog sleeps on the bed?
Probably, yes. A dog that settles across the foot or between you eats into the 67.5cm each a UK double allows, and the UK king's 75cm per sleeper restores some of that. The firm, evenly supported open coil surface also copes well with weight landing in odd places at 3am.