What Are the Dimensions of a King Size Bed UK?

A UK king size bed measures 5ft by 6ft 6in, which is 150cm wide by 200cm long. That is 15cm wider and 10cm longer than a standard UK double, which measures 135cm by 190cm. The extra length is often the more valuable of the two, since it is the point at which UK bed sizes step up from 190cm to 200cm.

Those figures describe the mattress. The bed frame will always be larger, and the difference between mattress size and overall footprint is what decides whether a king size bed fits your bedroom comfortably or simply fits it.

King Size Mattress and Frame Footprint

At 150cm by 200cm, a king mattress gives each sleeper 75cm of width, which is the same as a small single bed each. That is a meaningful improvement on a double, where each person has 67.5cm.

Frames add to this. A slim wooden or metal frame typically brings the total width to around 158cm to 165cm. An upholstered frame with padded side rails can reach 175cm or more. Length grows too: a padded headboard adds 8cm to 15cm, and a footboard or upholstered foot rail adds a similar amount at the other end. It is entirely possible for a king size bed to occupy 175cm by 225cm of floor once the frame is accounted for.

This is why the overall dimensions on a product page matter more than the mattress size. Our king size fabric beds UK sale list external measurements alongside the mattress size, which lets you compare a slim design against a deeply upholstered one before deciding.

What Room Size Do You Need?

As a working guide, a king size bed suits a bedroom of around 3m by 3.4m or larger. In that space you can place the bed against one wall and keep a walkway of roughly 70cm on both sides and at the foot, which is comfortable for making the bed and opening wardrobe doors.

A room of about 3m by 3m can take a king, but something has to give: usually the foot end walkway becomes tight, or one side sits closer to the wall than is ideal. A room under 2.8m in width will feel cramped with a king in it, and a smaller size will make the room more usable.

Practical minimums are worth knowing. Allow 60cm as the smallest comfortable walkway, and 50cm as the absolute minimum on a side you rarely use. Remember that a walkway is measured from the outside of the frame, not the mattress, and that a wardrobe door swinging into it needs its own clearance on top.

Also check the diagonal route into the room. A king mattress is 200cm long and cannot be bent. It needs to clear the doorway, any turn on the landing, and the swing of the bedroom door. Mattresses in a roll pack are easier here, but a traditional sprung king mattress needs a genuine straight run.

UK King Compared With Other Sizes

The UK bed range runs as follows: small single 75cm by 190cm, single 90cm by 190cm, small double 120cm by 190cm, double 135cm by 190cm, king 150cm by 200cm, and super king 180cm by 200cm.

Two things stand out. First, king and super king are the only common sizes at 200cm long, which makes either a sensible choice for anyone over about 6ft. Second, the jump from king to super king is 30cm of width, twice the step from double to king. If the room can take it, that extra width is significant, though it also demands wider bedding and a larger walkway allowance.

UK king is not the same as sizes sold under similar names elsewhere. A European king and a US king both differ in width or length, so a mattress bought under one convention will not sit correctly in a frame built to another. Always match frame and mattress to the same UK size, and buy bedding labelled for UK king.

Bedding for a UK King

A king duvet measures 225cm by 220cm, which gives good drape on both sides of a 150cm mattress. Fitted sheets must be bought in UK king size, and if your mattress is deeper than about 25cm, look for a deep fitted sheet so the corners do not pull off during the night.

Pillows are where people go wrong. A king bed at 150cm wide suits two king size pillowcases at 50cm by 90cm, or three standard pillows across the width. Two standard pillows at 50cm by 75cm leave a visible gap in the middle, which is why a made king bed sometimes looks unfinished. Adding a pair of larger pillows behind the sleeping pair fills the width and gives a tidier line.

Mattress protectors and toppers follow the same rule as sheets: buy UK king specifically, and check the depth.

Choosing the Right King Size Frame

Once you know a king fits, the frame decision comes down to style, storage, and how much visual weight the room can carry.

Upholstered frames bring warmth and a soft edge, which suits a bedroom intended to feel restful. They are also the frames that add most to the external footprint, so measure carefully. Wooden frames tend to be slimmer and read as calmer in a room with a lot of texture elsewhere. Our king size wooden beds UK sale include low platform designs that suit rooms with lower ceilings, where a tall headboard would crowd the wall.

Storage is worth planning at the same time. A raised king frame leaves useful space beneath for boxes, while a low platform design does not. If the room has limited wardrobe space, pairing the bed with a modern chest of drawers UK sale at standing height is usually more practical than relying on under bed storage alone.

Bedside furniture needs rethinking at king size too. A 150cm bed with narrow cabinets either side can look under scaled. Slightly wider cabinets balance the proportions better, and our bedside cabinets UK sale range includes options in matching finishes so the group reads as one arrangement rather than three separate pieces.

Laying Out a King Size Bedroom

Centring the bed on the longest uninterrupted wall usually produces the calmest layout, with symmetrical bedside cabinets either side. If a chimney breast or window prevents that, shifting the bed off centre and using a single bedside cabinet reads better than forcing symmetry into a space that cannot hold it.

At the foot of the bed, resist filling every centimetre. A bench or a slim ottoman UK sale gives somewhere to sit and to put a folded throw, but only where the walkway remains usable. In a tighter room, leaving the foot end clear makes the whole space feel larger than any additional piece would.

Lighting matters more with a wide bed, because a single central ceiling light leaves both sides poorly lit for reading. Wall lights or a pair of table lamps solve it and free up the surface of the bedside cabinets. You can shop modern furniture for the whole bedroom at Furniture in Fashion, with free delivery to most UK mainland postcodes.

Frequently Asked Questions

What are UK king size bed dimensions in cm?

A UK king mattress is 150cm wide by 200cm long, equivalent to 5ft by 6ft 6in.

Is a UK king bigger than a double?

Yes. A king is 15cm wider and 10cm longer than a UK double, giving each sleeper 75cm of width instead of 67.5cm.

What room size do I need for a king size bed?

Around 3m by 3.4m gives comfortable walkways on both sides and at the foot. A 3m by 3m room can work, but the foot end will feel tight.

Is a UK king the same as a European or US king?

No. The widths and lengths differ between conventions, so match your frame, mattress, and bedding to UK king specifically.

How many pillows fit across a UK king bed?

Two king size pillows at 50cm by 90cm span the width neatly, or three standard pillows will fill it. Two standard pillows leave a gap in the centre.