What Width Is a King Size Bed?

A UK king size bed is 150cm wide, which is 5ft. The full mattress size is 150cm x 200cm, so the length is 200cm or 6ft 6in. Split between two sleepers, that 150cm gives 75cm each.

The width is the figure that separates a king from a double, since both are available in similar frame styles and the length difference is smaller. Understanding what 150cm means in a real bedroom is what tells you whether the upgrade is worth making.

What 75cm Each Actually Feels Like

Comparisons help here. A standard single mattress is 90cm wide, so each sleeper on a king has 15cm less than they would sleeping alone on a single. On a double at 135cm, each person has 67.5cm, so a king adds 7.5cm each.

That 7.5cm sounds minor written down. In practice it is the difference between two side sleepers touching shoulders and having clear space between them. Most couples who move from a double to a king notice it immediately, particularly if one of them is a restless sleeper.

Build matters. Broader shoulders take up more of the available width, and side sleepers who bring their arms forward need more than back sleepers do. If either of you regularly wakes up on the edge of the mattress, the width is the thing to change.

Motion transfer interacts with width too. Pocket springs work independently and reduce movement across the bed, so a pocket sprung king feels considerably more spacious in use than an open coil one of the same dimensions.

The Width Ladder Across UK Sizes

All five UK widths: single 90cm, small double 120cm, double 135cm, king 150cm, super king 180cm.

The steps are uneven. From single to small double is 30cm, small double to double is 15cm, double to king is 15cm, and king to super king is 30cm. So the largest jumps are at the bottom and top of the range.

Length is a separate matter. Single and small double are 190cm, double is 190cm, and king and super king are both 200cm. That means the double to king step gains 10cm of length as well as 15cm of width, whereas the king to super king step gains width only.

If length rather than width is your concern, a king is the entry point to the 200cm sizes and there is nothing longer in the standard range.

External Width and Fitting Into a Room

The 150cm figure is the mattress. Frame width depends on the construction and always exceeds it.

Upholstered frames with deep padded side rails commonly add 10cm to 20cm, giving an external width of 160cm to 170cm. Wooden frames with substantial posts sit at the upper end. Metal frames add the least, sometimes 5cm. Divan bases are flush with the mattress, so the base is 150cm and only the headboard projects.

This distinction is critical where the bed sits between fitted wardrobes or in an alcove. Measuring the recess against 150cm and ordering an upholstered frame is a common and expensive mistake. Take the external figure from the specification every time.

Our modern king size leather beds UK sale range publishes external dimensions alongside mattress sizes so you can check the fit before ordering.

Room Width Calculations

Allow 60cm to 75cm of clear floor on each side you need to walk down. That is enough to pass comfortably and to change the bedding without awkward shuffling.

With access on both sides: 165cm external frame plus two 65cm walkways gives 295cm. So a room of roughly 3m width takes a king comfortably with access all round.

With one long side against a wall: 165cm plus one 65cm walkway gives 230cm. A room of 2.3m width handles it, which brings a king within reach of many second bedrooms.

Watch the obstacles. An inward opening door needs its full arc kept clear. A radiator reduces the usable width at skirting level. A chimney breast narrows the span at one point, and that point is what governs.

Marking the footprint on the floor with masking tape and walking around it for a day tells you more than any calculation. It is the single most useful thing you can do before ordering a bed.

Storage Choices at King Width

The 150cm x 200cm area under a king is substantial storage in a house without a loft or spare room.

Ottoman lift up bases give you the whole footprint as one cavity, accessed by lifting the base on gas struts. They take bulky items such as spare duvets and suitcases. The base needs clearance at the foot or side to swing up, and the bed must be clear of clutter to open it.

Drawer bases divide the space into pull out sections. Access is easier for everyday items, but each drawer needs its full depth of clear floor in front. In a room where one side of the king sits against a wall, those side drawers become unusable.

Open leg frames offer no built in storage but make a room feel lighter because floor is visible beneath the bed. In a 2.3m wide bedroom where a king already dominates, that visual relief can be worth more than the storage.

Choosing Furniture for the Remaining Space

A king at 150cm plus frame overhang leaves limited wall for bedside furniture. Cabinets of 35cm to 45cm fit without narrowing the walkway unduly.

Height matters as much as width. The cabinet top should sit level with the finished mattress top, so add frame height to mattress depth before choosing. Our bedside cabinets UK sale range lists heights for every model.

For clothing, tall narrow chests are more efficient than wide low ones where wall space is short. Our modern wooden chest of drawers UK sale collection includes upright designs suited to a king sized bedroom.

A mirror opposite the window bounces daylight and makes a room feel wider than its measurements, which counters the visual weight of a large bed. Our bedroom mirrors UK sale range covers wall mounted and freestanding designs.

Bedding is the last practical point. King fitted sheets are cut for 150cm x 200cm and duvets are typically 225cm x 220cm. Double bedding will not stretch across the extra 15cm.

Compare every UK width in our full modern beds UK sale collection. At Furniture in Fashion you can shop modern furniture across every room, with free delivery to most UK mainland postcodes.

Frequently Asked Questions

What width is a king size bed in the UK?
150cm, which is 5ft. The mattress length is 200cm, or 6ft 6in.

How much wider is a king than a double?
15cm wider, going from 135cm to 150cm. That gives each sleeper 7.5cm more space.

How much room does each person have on a king bed?
75cm each, which is 15cm less than the width of a standard single mattress.

What room width do I need for a king size bed?
Around 3m for access on both sides, or 2.3m with one long side against a wall.

Does the frame make a king wider than 150cm?
Yes. Expect 160cm to 170cm externally on upholstered and wooden frames. Divan bases stay flush at 150cm.