Standard British mattress sizes are single (90 × 190 cm), small double (120 × 190 cm), double (135 × 190 cm), king (150 × 200 cm) and super king (180 × 200 cm). The question we are asked most is double bed mattress measurements, and the answer is 135 cm × 190 cm, or 4ft 6in × 6ft 3in. Full UK mattress dimensions in centimetres and inches are charted below, along with how to measure your bed frame before you buy.
Standard UK mattress sizes at a glance#
UK mattress sizes are standardised, though there is some variation between brands (particularly at the edges of the size range). Every standard size, with mattress dimensions in both centimetres and inches:
| Size | Imperial name | Dimensions (cm) | Dimensions (inches) |
|---|---|---|---|
| Small single | 2ft 6in | 75 × 190 cm | 29.5 × 74.8 in |
| Single | 3ft | 90 × 190 cm | 35.4 × 74.8 in |
| Small double | 4ft | 120 × 190 cm | 47.2 × 74.8 in |
| Double | 4ft 6in | 135 × 190 cm | 53.1 × 74.8 in |
| King | 5ft | 150 × 200 cm | 59.1 × 78.7 in |
| Super king | 6ft | 180 × 200 cm | 70.9 × 78.7 in |
| Emperor | 6ft 7in | 200 × 200 cm | 78.7 × 78.7 in |
Small single and emperor are specialist sizes: most UK retailers stock single through super king as standard.
What are double bed mattress measurements?#
A UK double mattress measures 135 cm × 190 cm, which is 4ft 6in × 6ft 3in, or roughly 53 × 75 inches. It is the most common mattress size in Britain and the one most bedding, protectors and fitted sheets labelled "double" are cut for.
Two points catch people out. A UK double is not the same as a EU double (140 × 200 cm) or a US full (137 × 191 cm), so imported frames and bedding rarely fit properly. And at 135 cm wide, a double gives two adults 67.5 cm each, which is less than the 90 cm each of them would get in a single bed.
Choosing the right size for one person#
For a solo sleeper, a single is fine if space is very limited (e.g., a small bedroom or child's room). However, most adults find a small double or double far more comfortable for everyday adult use, you can spread out, take different positions and still have space. A single is too narrow for regular adult sleep if you have any alternative.
Choosing the right size for two people#
A standard double (135 cm wide) gives each sleeper only 67.5 cm, less than a single bed's 90 cm. For couples who value sleep quality, a king size (150 cm) is the practical minimum, and a super king (180 cm) is the ideal if the room can accommodate it.
Note: if you go super king, you'll need two 90 cm × 200 cm single duvets rather than one super king duvet, as super king duvets are harder to find and often more expensive.
Length considerations for tall sleepers#
Standard UK mattresses are 190 cm long. This is fine for most people but can be restrictive if you're over 6 feet (183 cm) tall, especially since you need clearance beyond the top of your head. King and super king mattresses are 200 cm long, which makes a noticeable difference for taller sleepers. If you're 6ft 3in or over, look for a mattress that is 200 cm or longer.
UK vs EU vs US sizes#
Sizes differ significantly between countries. UK sizes do not match US or EU sizes, which matters if you're buying bedding abroad or using an imported bed frame:
- UK Double (135 × 190 cm) ≠ EU Double (140 × 200 cm)
- UK King (150 × 200 cm) ≠ US King (193 × 203 cm)
- UK Super King (180 × 200 cm) ≈ US California King (183 × 213 cm)
Always check the dimensions in centimetres rather than relying on size names when buying a mattress for a European or imported bed frame.
How to measure for a new mattress#
Before buying, measure your bed frame's internal dimensions (the area where the mattress sits). Allow a tolerance of 1–2 cm on each side. Most UK bed frames are designed to UK standard sizes, but older or bespoke frames may vary. Also measure the height of your room if buying a high-profile mattress, especially if you have a divan with a deep base.
Which size, and what we would put on it#
Once you know the dimensions, the question is which size suits your room and sleepers. Here is the quick decision, with a catalogue pick for each size.
| Size | Dimensions | Best for | Our pick |
|---|---|---|---|
| Small single | 75 × 190cm | Young children, cabin beds | Core CoolMax Memory Foam |
| Single | 90 × 190cm | Children, guest rooms, one adult in a small room | Superior Cashmere |
| Small double | 120 × 190cm | One adult who wants space; a tight second bedroom | Emma Original |
| Double | 135 × 190cm | One adult comfortably; two adults adequately | Luxe Velour Hybrid |
| King | 150 × 200cm | Most couples | Emma Original Pro |
| Super king | 180 × 200cm | Couples who are tall, restless or share with children | LuxeErgo 3400 Hybrid |
Leave at least 60cm of walking space on each side you need to get in from, and 90cm at the foot if there is a wardrobe. Measure the room, then the stairs and doorways for delivery. Our delivery guide covers the access question.
Frequently asked questions#
What are UK mattress dimensions in inches?#
Single 35.4 × 74.8in, small double 47.2 × 74.8in, double 53.1 × 74.8in, king 59.1 × 78.7in and super king 70.9 × 78.7in. British mattress sizes are specified in centimetres, so inch figures are converted and rounded, always buy to the centimetre measurement.
How do I measure a mattress correctly?#
Measure the width and length of the sleeping surface, edge to edge, not the bed frame, and measure the depth separately from the base of the mattress to the top of the surface. Depth decides which fitted sheets will fit: anything over about 25 cm needs deep-fitted sheets.
What are the standard UK mattress sizes?#
Small single 75 × 190cm, single 90 × 190cm, small double 120 × 190cm, double 135 × 190cm, king 150 × 200cm and super king 180 × 200cm. Emperor (200 × 200cm) is a non-standard luxury size.
What size mattress should a couple buy?#
King if the room allows. A double gives two adults less width each than a single bed. Super king is worth it for tall, restless or heavier sleepers, or if children join you.
Is a UK king the same as a US or EU king?#
No. A UK king is 150 × 200cm; an EU/IKEA king is 160 × 200cm; a US king is 193 × 203cm. Names are unreliable; always compare centimetres.
How much room does a bed need?#
The mattress plus 60cm on each side you get in from, plus 60–90cm at the foot for drawers or a wardrobe. A king therefore needs a room at least 2.7m wide; a super king about 3.0–3.3m.
Related reading#
- EU size mattress guide – IKEA and European frames
- Best king size mattress – the size most couples should buy
- Best small double mattress – the 120cm option
- Best mattress for couples – the size and motion isolation question
- Mattress delivery in the UK – will it get up the stairs?
