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). Here are the standard dimensions:

  • Single: 90 cm × 190 cm (3ft × 6ft 3in)
  • Small single: 75 cm × 190 cm (2ft 6in × 6ft 3in) — less common
  • Small double (4ft): 120 cm × 190 cm (4ft × 6ft 3in)
  • Double: 135 cm × 190 cm (4ft 6in × 6ft 3in)
  • King size: 150 cm × 200 cm (5ft × 6ft 7in)
  • Super king: 180 cm × 200 cm (6ft × 6ft 7in)
  • Emperor: 200 cm × 200 cm (6ft 7in × 6ft 7in) — specialist size

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.