What size is a UK single mattress?

A UK single mattress is 3ft (90cm) wide by 6ft 3in (190cm) long. A small single is 2ft 6in (75cm) wide, sometimes called a shorty for under-15 frames. Standard single and small single are not interchangeable; the 15cm width gap is the most-returned-by-mistake mattress in our category.

Can an adult sleep on a single mattress long-term?

Yes, but the spec matters. Pocket sprung 800+ or hybrid foam in the £200 to £400 band is the realistic floor. Foam-only and budget bonnel-spring under £100 are built for spare-room duty, not 7 nights a week. Most British single adults who use a single long-term are in studio flats or box rooms where a small double will not fit.

When should a child's single mattress be replaced?

Every 7 to 8 years per the Sleep Council, or sooner if growth has hit. Children outgrow the support of a thin or mid-range mattress by age 11 to 13 as adult body weight comes in. Watch for visible sagging, a dip in the middle, or springs you can feel through the cover.

What size mattress fits the top bunk of a bunk bed?

Most bunk frames cap the top mattress at 15cm or 18cm depth, marked on the spec page. Anything thicker reduces the safety rail's effective height below the BS EN 747 standard. A 13cm to 15cm pocket sprung or foam mattress is the safe bet. Measure the rail-to-bed-base gap before ordering.

What's the difference between a small single and a standard single?

A small single is 75cm wide (2ft 6in); a standard single is 90cm wide (3ft). Both are 190cm long. Small single is narrower for box rooms, narrow bunk frames and toddler beds graduating from a cot. Bedding is sized separately; small-single sheets will not fit a standard single.