Short answer: a small double bed is 4ft wide by 6ft 3in long, which is 120cm by 190cm, or 47 by 75 inches. It is the size people mix up most, because it is not a double: a double is 4ft 6in (135cm) wide. Here is the whole set of UK bed sizes.
UK standard bed and mattress sizes
| Name | Feet and inches | Centimetres | Inches |
|---|---|---|---|
| Small single | 2ft 6in x 6ft 3in | 75 x 190 | 30 x 75 |
| Single | 3ft x 6ft 3in | 90 x 190 | 36 x 75 |
| Small double | 4ft x 6ft 3in | 120 x 190 | 47 x 75 |
| Double | 4ft 6in x 6ft 3in | 135 x 190 | 54 x 75 |
| King | 5ft x 6ft 6in | 150 x 200 | 60 x 78 |
| Super king | 6ft x 6ft 6in | 180 x 200 | 72 x 78 |
Mattresses and divan bases are made to these sizes, so a king mattress fits a king base from any maker. Bed frames are made around them, so a king frame is a few centimetres bigger than a king mattress on the outside.
Small double vs double: what is the difference?
A small double is six inches (15cm) narrower than a double and the same length. It exists for box rooms, tenement bedrooms and for one person who wants space. Two adults on a small double is tight; two adults on a double is the standard. If you are buying online and the price looks too good, check it is not a small double. We have a separate guide on small double or double for a tenement bedroom.
Is a 4ft 6 bed a small double?
No. A 4ft 6in bed is a standard double. A small double is 4ft. The names are confusing because a small double is also called a three-quarter bed or a queen in some older catalogues. If your bed is 120cm wide it is a small double; if it is 135cm wide it is a double.
Will double bedding fit a small double?
A double fitted sheet will go on a small double mattress but it will be baggy, and a double duvet will hang further over the sides. Most people use double duvets on a small double without any bother. For fitted sheets, small double sizes are sold by most bedding shops and fit much better.
The other ones people get wrong
King versus super king. A king is six inches wider than a double and three inches longer. A super king is another foot wider again, so wide that many bedrooms cannot take it with bedsides either side. It is also usually the size where the base and mattress come in two halves to get up the stairs.
Length. Single, small double and double are 6ft 3in long. King and super king are 6ft 6in. If someone in the bed is over six foot, a king is longer as well as wider, which is often the real reason to buy one.
European sizes. IKEA and some online retailers sell European sizes: a Euro double is 140 x 200 and a Euro king is 160 x 200. They do not fit UK bases or UK bedding. If your bed came from IKEA, measure it before buying a mattress.
How to measure the bed you have
Measure the mattress, not the frame, from edge to edge, in centimetres. Round to the nearest size in the table. If it does not land near any of them, it is probably a European size or a very old bed. If the mattress is on a divan base, the base is the same size as the mattress.
Which size should you buy?
One adult: a small double if the room allows it, otherwise a single. Two adults: a king if the room takes it, otherwise a double. The difference between a double and a king for two people is the difference between touching all night and not. Most couples who move up to a king say they wish they had done it years earlier.
A quick way to check a king will fit: the mattress is 150cm wide, add 45cm for a bedside table each side and you need a wall at least 240cm wide, plus room to walk round the end.
Frequently asked questions
What size is a small double in cm? 120cm wide by 190cm long.
What size is a small double in inches? 47 inches wide by 75 inches long.
Is a small double the same as a queen? In the UK, some older retailers called a 4ft bed a queen. It is the same size as a small double. It is not the same as an American queen, which is 60 x 80 inches.
Can two adults sleep on a small double? They can, but it is tight. A double is the usual minimum for two, and a king is more comfortable.
Every size in this table is on the floor in our Clydebank showroom, most of them in several models, so you can lie on a double and a king next to each other and see the difference rather than imagine it. Browse small double mattresses, king size mattresses or the full mattress range from £299, and complete beds from £449.
Paul James Home, inside the Co-op Department Store, Clydebank. Monday to Saturday 9 to 5. 0141 266 0400.
