Bed Sizes: Single, Small Double, Double, King and Super King

There are five standard bed sizes sold in the UK, and the difference between each one and the next is always width. Length changes only once across the whole range, which is the single most useful thing to know before choosing — and the thing most size guides bury.

What follows compares all five, so you can settle the size before looking at a single frame.

UK bed sizes in order

Where the length changes

Single, small double and double are all 6ft 3in long. King and super king are both 6ft 6in. That means moving from a small double to a double, or from a king to a super king, gains you width and nothing else — while moving from a double to a king is the only step in the range that gains you both.

It follows that if the problem is a sleeper who reaches the end of the bed, only one upgrade solves it. Going from a double to a super king costs a foot and a half of floor and buys the same 3 inches of length that a king would have.

What each size gives two people

The final column above is the number that decides most of these choices, and it is worth sitting with. A single bed gives one person 36 inches. A super king gives each of two people exactly that same 36 inches. Everything between is a compromise against that figure, and a double — the size most couples sleep in — gives each person 27 inches, three quarters of what one person has alone in a single.

Those figures are also the hardest thing on this page to picture, because six inches sounds like nothing written down and reads very differently when you are standing beside it. Our Enniskillen showroom has the sizes made up alongside one another, and a couple of minutes moving between them tends to settle a decision that a table of numbers only complicates.

Is there a queen size bed in the UK?

No. Queen is a North American size, 60 inches by 80 inches, and it does not exist in UK retail. The closest UK equivalent is a king size at 5ft by 6ft 6in, which is slightly narrower and slightly longer. If you have seen a bed described as queen size on a UK site, it is usually either an import or a loose use of the word, and the measurements are what to check rather than the name.

What is the biggest bed size in the UK?

Super king, at 6ft by 6ft 6in, is the largest size sold as standard. Larger beds exist — emperor and caesar sizes among them — but they are made to order rather than stocked, and mattresses and bedding for them are specialist purchases.

How much room each size needs

Allow 24 inches (60cm) of clear floor on every side someone gets in or out from, and at the foot if there is anything to walk past. Applied across the range, that means a bed needs roughly 4ft more than its own width to sit comfortably in a room used by two people.

Two things catch people out regardless of size. The frame is always wider than the mattress it holds — an inch or two on a slim wooden frame, four or five on an upholstered one with padded sides — so the size on the label is not the size in the room. And wardrobe and chest doors need their swing measured against the gap beside the bed, which is where most bedroom planning goes wrong.

What else changes with size

Two practical things scale with the bed and are worth knowing before committing to a large one.

The first is support. A frame that is perfectly sound at 3ft or 4ft 6in is being asked to do considerably more at 5ft and 6ft, where the slats span further and the side rails carry more. From king size upwards a centre support with its own legs to the floor stops being a refinement and becomes structural.

The second is everything you buy afterwards. Mattresses, fitted sheets, duvets and protectors are cheapest and most widely stocked in double and king, and get progressively harder to find and dearer either side of that — small double is a narrower market than double, and super king narrower still. It is a running cost rather than a one-off, and it is worth knowing before rather than after.

Choosing between the five sizes

For one person, a single at 3ft is generous for a child and tight for an adult over six foot, who will reach the end of the mattress. Our single beds cover 3ft frames with and without storage.

For two people occasionally, or one person who wants room to spread out, a small double at 4ft is the size that turns a spare room into a bed a couple can genuinely stay in. Our small double beds cover the 4ft range.

For two people every night, a double at 4ft 6in is the UK standard and the size most bedrooms are built around. Our double beds cover the 4ft 6in range.

Where the room takes it, a king at 5ft gives each person 3 inches more across and the whole bed 3 inches more length, which is the only upgrade in the range that helps a tall sleeper. Our king size beds cover the 5ft range.

And where the room is genuinely large, a super king at 6ft gives each of two people the same width one person has in a single. Our super king beds cover the 6ft range.

Bed size FAQs

What are the UK bed sizes?

Single 3ft by 6ft 3in, small double 4ft by 6ft 3in, double 4ft 6in by 6ft 3in, king size 5ft by 6ft 6in, and super king 6ft by 6ft 6in. In metric that is 90, 120, 135, 150 and 180cm wide, by 190cm for the first three and 200cm for the last two.

Which UK bed sizes are the same length?

Single, small double and double are all 6ft 3in. King and super king are both 6ft 6in. So the only step that adds length is moving from a double to a king.

Is a queen size bed the same as a UK king?

Not quite. Queen is a North American size at 60 by 80 inches, and it is not sold as standard in the UK. A UK king is 5ft by 6ft 6in, which is a little narrower and a little longer. Compare the measurements rather than the names.

How much space should you leave around a bed?

At least 24 inches (60cm) on each side someone gets in and out from, and the same at the foot if you walk past it. Remember the frame is wider than the mattress, and check wardrobe and drawer swings against the gap beside the bed.

Which bed size is best for a couple?

A double is the UK standard and suits most couples. A king adds 3 inches of width each and 3 inches of length, which is worth it if either of you is tall or sleeps restlessly and the room allows it. A small double works for occasional shared use but is tight for two adults every night.

Do bigger beds cost more to run?

In a sense, yes. Mattresses and bedding are most widely stocked and cheapest in double and king, and both get harder to find and more expensive in small double and super king. It is worth factoring in, since bedding is replaced several times over the life of a frame.