02 Aug 2026
UK Bed Sizes: A Complete Guide to Mattress and Frame Sizes
The four most common UK bed sizes are single (90 x 190cm), double (135 x 190cm), king (150 x 200cm) and super king (180 x 200cm). Those figures describe the mattress, not the bed frame — the frame around it is always larger, often by 10cm or more on each side. This guide sets out every bed size we sell, in centimetres and inches, and how to work out which one will genuinely fit your room.
UK bed sizes at a glance
UK mattress sizes are an industry standard. A double mattress bought anywhere in the UK should measure 135 x 190cm, which is why replacement mattresses and fitted sheets are interchangeable between brands. The imperial figures below are the traditional trade names and are rounded; the metric measurement is the accurate one.
| Size | Metric (W x L) | Imperial (approx.) | Sleeps |
|---|---|---|---|
| Small Single | 75 x 190cm | 2ft 6in x 6ft 3in | 1 child or adult |
| Single | 90 x 190cm | 3ft x 6ft 3in | 1 |
| Three Quarter | 107 x 190cm | 3ft 6in x 6ft 3in | 1 generously |
| Small Double | 120 x 190cm | 4ft x 6ft 3in | 2 at a squeeze |
| Double | 135 x 190cm | 4ft 6in x 6ft 3in | 2 |
| King | 150 x 200cm | 5ft x 6ft 6in | 2 comfortably |
| Super King | 180 x 200cm | 6ft x 6ft 6in | 2 with room to spare |
| Emperor | 200 x 200cm | 6ft 6in x 6ft 6in | 2, or a family |
Two details worth noting. First, everything up to and including a double is 190cm long; king size and above gain an extra 10cm, which matters if you are over about six feet tall. Second, three quarter and emperor are the least standardised sizes in the trade — different makers use different widths — so treat those two rows as typical rather than guaranteed. Check the measurement, not the name, when buying bedding, and ask us to confirm before ordering either.
What each size actually suits
Small single and single
A small single at 75cm wide is the narrowest size made and is intended for a child's room, a box room, or a bunk. A standard single at 90cm is the workhorse: it suits a child moving out of a cot bed, a teenager, or a spare room. Both are the same 190cm length, so a single will still take an adult. Our children's beds are made in single and small double.
Three quarter and small double
These two sit in the gap between one sleeper and two. A three quarter, traditionally 3ft 6in, is a generous single — ideal for one adult who likes to spread out, or for a guest room. We offer it on mattresses rather than frames, and the name is used loosely across the trade, so confirm the width with us. A small double (120cm) is a genuine two-person bed for a room that cannot take a full double, giving each sleeper 60cm — best for one adult most of the time and two occasionally.
Double
At 135cm, the double is the default UK couple's bed and the size most bedrooms are designed around. Each person gets around 67cm. If either of you is a restless sleeper, or you share the bed with a dog, you will feel the difference moving up a size.
King and super king
A king adds 15cm of width and 10cm of length over a double. A super king adds another 30cm, giving each sleeper the width of a whole single bed. Both need a room that can take the extra footprint without crowding the door or wardrobes.
Emperor
An emperor is as wide as it is long. It suits large principal bedrooms and households where children and pets end up in the bed. Bedding usually has to be ordered specially.
Your bed frame is bigger than your mattress
This is the mistake that causes most returns. The sizes in the table are mattress sizes. A bed frame adds its own side rails, footboard and headboard, and how much it adds depends entirely on the design: a slim upholstered frame adds around 10cm on each side, while a deeply padded or winged design adds considerably more, and the headboard adds to the overall length as well.
Because our frames are made to order in a range of styles, external frame dimensions vary from model to model. Almost every bed frame we sell has a specifications tab on its product page listing the external width and length for the sizes it is quoted in — check those figures against your room before you order, rather than working from the mattress size alone. You can compare designs across our bed frames, and our divan beds list their own external dimensions in the same place. On some models the headboard width is quoted separately and is much wider than the bed itself, so read both figures. If the size you want is not listed there, ask us.
Choosing by room size: clearance matters more than floor area
Rather than asking whether a bed will fit, ask whether you can still use the room once it is in. A useful working figure is 60–75cm of walking space down at least one side of the bed and at the foot. Below about 50cm you will be turning sideways to get past, and making the bed becomes a chore.
A quick method that takes five minutes:
- Measure the room wall to wall, and note the door swing, the radiator and how far the wardrobe doors open.
- Add roughly 10cm to each side of your chosen mattress width as an allowance for the frame, then check the product specifications for the exact figure.
- Mark the resulting rectangle on the floor with masking tape and live with it for a day.
- Check that every door, drawer and window still opens fully with the tape in place.
As a rough guide, a room around 3.0 x 3.0m will take a double comfortably; a king generally wants something closer to 3.0 x 3.5m; and a super king or emperor is happiest in a room of 3.5 x 3.7m or larger. These are guides, not rules: a long narrow room may take a bigger bed than a square one of the same area. Allow for anything that lives at the foot of the bed, such as a blanket box or footstool.
Getting the bed into the room
The size that fits your bedroom still has to reach it. Before ordering a king or larger, measure:
- Doorways — width and height, including every one on the route.
- Stairwells — the turn at a half landing is usually the tightest point in a house.
- Ceiling height on the stairs — low ceilings stop a headboard being tipped upright.
- Lifts and communal corridors in flats, which often have a hard limit.
Some wide upholstered headboards are supplied split into bolt-together sections rather than as one panel; where that applies, the specifications tab says how many, so you can judge whether the pieces will make the turn. A mattress is the awkward item, particularly a super king or emperor, because it cannot be dismantled. If access is genuinely difficult, tell us before you order. Our delivery information page explains how deliveries work and what they cost.
Size, then everything else
Every bed we sell is made to order, and size is the first choice in the configurator. After that you choose your fabric and colour — typical lead time is four to six weeks. Nothing is held in stock, so the size you choose is the size you get.
Two things worth doing before you commit. Order fabric samples, which are £2.00 each, so you can see the colour in your own light rather than on a screen. And think about the mattress at the same time as the frame — the size has to match exactly, and depth affects how the finished bed looks against the headboard. You can see the options on our mattresses pages.
Quick answers
Is a UK king the same as a US king? No. A UK king is 150 x 200cm; a US king is wider. Bedding is not interchangeable.
What is the difference between a small double and a double? 15cm of width. A small double is 120cm, a standard double 135cm.
Which size should I choose if I am unsure between two? If the room takes the larger one with proper walking space down at least one side, take the larger one.