Single bed size guide

The one size where open coil makes sense

Everywhere else on this site, open coil is the wrong construction for a shared bed, because the springs are wired together and the surface responds as one sheet: one person turning over moves the other side.

On a single, there is no other side. So the main objection disappears, and what is left is a durable construction with thick wire, plenty of steel and no fabric pockets to wear.

The hourglass shape is progressive, resisting more the further it compresses, which is why open coil feels supportive rather than bottoming out. A good open coil single on a proper base will outlast cheap foam comfortably, and costs less.

The exception: if the single is for a side sleeper, pocket springs still contour better at the shoulder and hip.

What a single is actually for

Children past a cot bed. A child barely compresses a mattress, so a very high spring count does little for them and firm is the right specification. Waterproofing and a washable cover matter far more than count.

Guest rooms. Where the buying rule inverts: you cannot measure your guests, so medium-firm is genuinely correct rather than a compromise, and two medium pillows per person covers more people than one fixed height.

Adults in small rooms. At 90 centimetres, a single gives one adult more personal width than a double gives each of two, which is 67.5.

Bunks, trundles and day beds, where the frame usually caps the mattress depth well below what an adult bed takes.

A rarely used bed has different requirements

This inverts normal mattress advice and matters in a guest room.

Foam degrades with time as well as use. A foam mattress slept on sixty times over six years will still have aged six years, because the polymer breaks down whether anyone is on it or not. Steel does not.

So springs are worth paying for more in a spare room than in a main bed, which is the opposite of how people usually allocate the money.

Also: air it before guests arrive, rotate it head to foot a couple of times a year even though it is barely used, and fit a protector, because guests will not tell you about a spill and a stain voids most guarantees.

Small single, and when it is the right call

At 75 by 190 centimetres, a small single is 15 centimetres narrower than a standard single. It exists for box rooms, cabin beds and bunk frames.

The trade is real: bedding is stocked far less widely, so check that fitted sheets and a duvet are available in the size and depth you need before buying the bed.

One useful fact: two small singles pushed together make 150 by 190, which is king width and ten centimetres short of king length.

Check the frame's depth limit first

Singles disproportionately end up in frames that cap depth, and this is where people order a mattress that cannot be used.

Bunk beds state a maximum, commonly around 15 centimetres, because guard rail height is measured from the top of the mattress. Exceeding it is a safety matter, and a topper cannot be added for the same reason.

Trundles are limited by the clearance under the main bed, usually around 15 centimetres, and it has to slide back in made up with bedding on.

Day beds are limited by the back rail: a mattress reaching more than about half its height leaves nothing to lean against.

At shallow depths, firm works better than soft, because there is less material between the sleeper and the base.

European and US sizes with the same names are different

This is where most sizing mistakes come from, and it catches people buying from IKEA and from imported ranges.

Every row differs, and the length differs as well as the width on singles and doubles. A European double is ten centimetres longer than a UK one, which is the part people miss.

A US queen is roughly 152 by 203cm, closest to a UK king. There is no UK queen size, so a listing offering one is using an imported name.

Depth is the measurement nobody checks

Bed sizes describe length and width. Depth is not standardised at all, and it is what decides whether your sheets fit.

Standard UK fitted sheets are cut for about 25 centimetres. Modern hybrids run 28 to 35, and a topper adds 5 to 10 on top of that.

Add the mattress depth to the topper depth and buy a few centimetres over, because the fabric has to fold under rather than merely reach the edge.

Measure the base, not the old mattress

An old mattress has compressed and may have distorted, so measuring it gives you the wrong number.

Measure the internal dimensions of the bed frame, at the longest and widest points, and check the depth the frame will take.

Manufacturers vary by a centimetre or two even within standard sizes, which matters most on frames with a headboard and footboard where the mattress has to drop between them rather than sit proud.

Related reading

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