Horizon Odyssey 800 Pocket Memory Mattress
Mattress
Horizon Odyssey 800 Pocket Memory Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
23
Layers
2
Layer Details
- Memory Foam. A 2cm memory layer that contours to your body for personalised comfort and helps relieve pressure on joints, back and hips. It's a cooling layer too, which matters if you tend to sleep warm.
- Pocket Springs. 800 individual pocket springs that move independently, which means support tailored to where your body needs it and no motion transfer. In practice, you're less likely to feel a partner turning over.
Layer details from mattressonline.co.uk product page, September 2026.
- Spreading room for one: The UK small double is 30cm wider than the UK single, which means a solo adult can shift position freely without a bigger step up in frame size.
- Fits rooms a double crowds: At 15cm narrower than the UK double, this size can be the difference between a bedroom door clearing the frame or scraping it.
- Pocket springs across the full 4ft: All 800 springs move independently, so on the occasional night two people share, one turning over is less likely to disturb the other.
- Guest rooms and second bedrooms: Couples can manage a night or two at 120cm wide, making this a sensible pick for a spare room or holiday let that hosts visitors rather than residents.
- Standard bedding, easy to find: 4ft is a recognised UK size, so small double fitted sheets and frames are widely stocked, and a standard double duvet works on top.
This size suits you if...
You sleep alone and have outgrown a single but your room cannot spare the width of a full double, you're furnishing a box room, loft conversion or studio where every centimetre beside the bed matters, or you need a guest bed that handles the occasional visiting couple. Allow at least 2.4m x 2.8m of floor space and the UK small double sits comfortably.
Consider another size if...
You share the bed every night, because 120cm is tight for two long term. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m for it.
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Is a small double Horizon Odyssey 800 big enough for a couple?
For occasional nights, yes. The 800 pocket springs move independently, so you're less likely to feel a partner turning, but at 120cm wide two adults get noticeably less personal space than on a UK double. For nightly sharing we'd suggest sizing up; for a guest room, the UK small double is a practical fit.
What room size do I need for a small double mattress?
We suggest allowing at least 2.4m x 2.8m for the UK small double. That leaves enough space to open the door, walk around the bed and fit a bedside table. If your room is smaller than that, measure carefully before ordering, as a cramped layout undoes the benefit of the extra width.
How big is the Horizon Odyssey 800 in a UK small double?
It measures 120 x 190cm, which is 4ft x 6ft 3in. The depth is 23cm, the same across every size of this mattress. Length-wise it matches the UK single and UK double; the UK king and UK super king are 10cm longer if you're tall.
Is the small double good for a teenager upgrading from a single?
It's a sensible step. The UK small double is 30cm wider than the UK single but exactly the same length, so a teenager gains real room to spread out without the bed swallowing more floor space than a compact bedroom can give up. The medium firm feel suits most growing sleepers, though very light side sleepers may find it slightly firm.
What bedding fits the Horizon Odyssey 800 small double?
You'll need small double, or 4ft, fitted sheets, which are widely available from UK retailers. A standard double duvet is the usual pairing and gives a little overhang on each side. Standard double sheets will bag loosely, so it's worth buying the correct 4ft size for a tidy fit.