The UK Bed Size Comparison Tool: UK Mattress Dimensions

UK mattress sizes are standardised and they do not match European or American sizes. A UK king size measures 150cm x 200cm, a double measures 135cm x 190cm, and neither is interchangeable with the continental equivalents, which is the source of most bedding and mattress fit problems in British homes.

The more useful conclusion for anyone furnishing a bedroom is that the mattress size is decided by the room, not by preference. A bed needs a clear route on at least one long side and enough space for the wardrobe doors and drawers to open fully, and those requirements frequently cap the bed a room can take.

Key findings at a glance

• The standard UK sizes are single 90cm x 190cm, small double 120cm x 190cm, double 135cm x 190cm, king 150cm x 200cm and super king 180cm x 200cm.
• UK sizes differ from European ones: a European king is commonly 160cm x 200cm and a European double 140cm x 200cm, which is why imported bedding often fits poorly.
• Allow at least 70cm of clear floor on any side of the bed used for access, and 90cm where a wardrobe or chest of drawers opens onto that side.
• UK doubles and small doubles are 190cm long while king and super king are 200cm long, so the extra 10cm of length arrives only at king size.
• The Nationally Described Space Standard sets a minimum floor area for a single bedroom and a larger minimum for a double bedroom in new homes in England, which is why bedroom three in many new builds cannot take a double comfortably.
• Bed frames add to the mattress footprint, typically 5cm to 15cm on each dimension, and ottoman and storage frames need lifting clearance above and in front.
• Staircase turns, not bedroom doors, are the usual obstacle for a one-piece mattress in period housing, and rolled or foldable mattresses solve it.

The standard sizes, and what they mean in a room

The table below sets out UK mattress sizes with the room dimensions needed to use them properly. The room figures assume access on one long side and one end, with the head of the bed against a wall.

UK size	Mattress dimensions	In inches	Minimum practical room	Suits
Single	90cm x 190cm	3ft x 6ft 3in	210cm x 250cm	Children’s rooms, box rooms, guest rooms
Small double	120cm x 190cm	4ft x 6ft 3in	240cm x 250cm	Second bedrooms, single adults wanting space
Double	135cm x 190cm	4ft 6in x 6ft 3in	270cm x 260cm	The standard UK couple’s bed
King	150cm x 200cm	5ft x 6ft 6in	290cm x 280cm	Main bedrooms with clear space both sides
Super king	180cm x 200cm	6ft x 6ft 6in	320cm x 280cm	Larger main bedrooms and loft conversions

Why the room decides, not the sleeper

The temptation in a main bedroom is to buy the largest bed the wall will take. What that produces is a room where one person climbs over the other to get out, or where the wardrobe doors foul the mattress corner.

Access clearance is the governing figure. Allow 70cm of clear floor on any side used to get in and out of bed: that is enough to walk past and to make the bed without shuffling sideways. Where a wardrobe, chest or dressing table opens onto that side, increase it to 90cm, because a drawer front projecting 50cm into a 70cm gap leaves nothing to stand in.

This is where many UK main bedrooms settle on a double rather than a king. Moving from 135cm to 150cm takes 15cm from the clearance on one side, and in a room 3.0m wide that is often the 15cm that made the wardrobe usable. Slim sliding wardrobes UK resolve the conflict directly, because sliding doors need no swing clearance at all.

Bedroom three and the small double

The second and third bedrooms of British houses are where sizing becomes genuinely difficult. The Nationally Described Space Standard sets minimum floor areas for single and double bedrooms in new homes in England, and the smaller of those is not intended to hold a double bed with circulation around it.

In older housing the equivalent room is the box room above the stairs, often under 2.4m in one direction. In both cases the small double at 120cm wide is the size that most often rescues the room: it gives 15cm more sleeping width than a single while taking 15cm less than a double, and it fits where a double will not. It is also the size most frequently overlooked, because buyers think in terms of single or double alone.

For children’s rooms, a single with under-bed storage or a bunk arrangement recovers the floor that a small room cannot otherwise spare, and options across single wooden beds UK include frames designed with drawers built in.

Frames, storage and the space you forget

The mattress is not the footprint. A bed frame adds to both dimensions, typically 5cm to 15cm per side depending on the design, and a substantial upholstered frame with a deep surround can add more. A headboard adds 5cm to 10cm at the head, which matters when the bed sits between a chimney breast and a wall.

Storage frames introduce a clearance nobody measures. An ottoman bed lifts the entire mattress platform on a gas mechanism, so it needs vertical clearance above the bed, which is a real constraint under a sloping loft ceiling. A drawer divan needs floor clearance in front of the drawers, typically 60cm to 70cm, and a drawer on the side against a wall is a drawer you will never open. Ranges of ottoman beds UK and drawer frames are worth checking against these clearances before ordering rather than after.

What this means for UK homes

Measure the room and subtract the clearances first: 70cm on each access side, 90cm where storage furniture opens. Whatever rectangle remains sets your maximum bed footprint, and then subtract the frame allowance to reach the mattress size.

Buy mattress, frame and bedding in the same size convention. UK sizes are not European sizes, and a continental king will not take UK king fitted sheets or sit correctly in a UK king frame. Check the label rather than the description.

Check the route before delivery. In period houses the tight turn at the head of the stairs, not the bedroom door, is what stops a one-piece mattress, and ceiling height at the turn matters as much as width. Rolled mattresses and knock-down frames pass where solid ones do not.

In smaller second bedrooms, consider the small double before defaulting to a single or forcing a double. It is the size that most often makes a difficult room work, and it takes standard 4ft bedding that is widely available.

Methodology

This 2026 comparison was compiled by our editorial team as a UK furniture retailer. It uses the standard UK mattress and bed sizes, their metric and imperial equivalents, standard bed frame allowances and the access clearances used in bedroom specification, applied to the room proportions typical of UK terraced, semi-detached, flatted and new build housing, with reference to the minimum bedroom floor areas set by the Nationally Described Space Standard in England. Recommendations reflect our editorial judgement from advising customers on bedroom fit. It contains no proprietary sales data, no customer data and no survey fieldwork, and no figures have been estimated.

Citing this report

Journalists and websites may cite this 2026 comparison with credit to Furniture in Fashion and a link back to this report. It is a specification-led editorial guide to UK mattress dimensions and bedroom fit, not a statistical study, and we ask that it is described as such.

Frequently asked questions

What are the standard UK bed sizes?

Single is 90cm x 190cm, small double 120cm x 190cm, double 135cm x 190cm, king 150cm x 200cm and super king 180cm x 200cm. Doubles and smaller are 190cm long, while king and super king extend to 200cm.

Is a UK king the same as a European king?

No. A UK king is 150cm x 200cm while a European king is commonly 160cm x 200cm, and a European double is usually 140cm x 200cm against the UK double’s 135cm x 190cm. Bedding and mattresses are not interchangeable between the two conventions.

How much space do you need around a bed?

Allow at least 70cm of clear floor on any side used for getting in and out. Increase that to 90cm where a wardrobe, chest of drawers or dressing table opens onto that side, so drawers and doors can be used fully.

What size bed fits in a small second bedroom?

A small double at 120cm x 190cm is often the answer. It gives more width than a single while fitting rooms that cannot take a 135cm double with circulation space, and it uses widely available 4ft bedding.

Does the bed frame change the size I need?

Yes. Frames typically add 5cm to 15cm to each dimension, and headboards add a further 5cm to 10cm at the head. Ottoman frames also need vertical lifting clearance, and drawer divans need 60cm to 70cm of clear floor in front of the drawers.