UK Bed Sizes: The Bed And Mattress Size Guide

So you’re buying a new bed or mattress, but you’re not sure about what the different bed sizes are. "Is there a standard size?" "Do I have to buy my bed frame and mattress at the same time?" "How big are king size bed dimensions compared to a standard double?"

It’s enough to stress anyone out, which is why we thought we’d put together this quick-reference guide to help you out.

In the UK, bed sizes are measured according to the size of the mattress they hold, which is a standard measurement. However, the actual dimensions of the bed frames can vary according to their shape and style, which is what can often cause confusion. A common mistake is to use the mattress size measurements for the required space, but you should always look at individual bed frame dimensions for exact measurements, as they will vary from frame to frame, and almost always be slightly larger than the mattress dimensions.

Most modern beds/mattresses sold in the UK (and Ireland) are constructed using imperial dimensions but are generally sold in their approximate metric equivalents:

Bed/Mattress Size Dimensions (Imperial) Dimensions (Metric)
Small Single 2'6'' x 6'3'' 75 x 190cm
Single 3'0'' x 6'3'' 90 x 190 cm
Small Double (Queen) 4'0'' x 6'3'' 120 x 190cm
Double 4'6'' x 6'3'' 135 x 190cm
King Size 5'0'' x 6'6'' 150 x 200cm
Super King Size 6'0'' x 6'6'' 180 x 200cm

Standard Bed & Mattress Sizes (UK)

What size is a small single bed and mattress?

Small single beds and mattresses are ideal for younger children or the petite. They measure in at 75cm wide and 190cm long. In imperial dimensions, this is equal to 2 feet 6 inches wide and 6 feet 3 inches long. Small single (2’6”) bed frames and mattresses work well in smaller bedrooms where space is tight. They are also a good ‘transition’ bed for young children moving from a cot into their first ‘grown-up’ bed.

Best for: Young children as a 'first grown-up bed', small rooms and guest beds

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What size is a single bed and mattress?

Suitable for both children and adults. A single bed and mattress measures in at 90cm wide and 190cm long. In imperial dimensions, this is equal to 3 feet wide and 6 feet 3 inches long. Single (3’0”) beds are wider than ‘small singles’ and provide a good amount of room for a single sleeper. This is the most common size for children’s beds, including bunk beds. For growing children, single beds can account for any growth spurts, from toddler right up through to teenage years.

Best for: 1 person

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What size is a small double (queen) bed and mattress?

In metric dimensions, a small double bed and mattress is 120cm wide and 190cm long. This equals to 4 feet wide and 6 feet 3 inches long. A ‘small double’ (4’0”) bed (also known as a ‘Queen’ or a ‘Three Quarter’) is wider than a single bed but smaller in width than a double. It provides plenty of space for one or enough room for two (although two adults may find it a little ‘cosy’). Great for smaller bedrooms and guestrooms where a standard double won’t quite fit. Where space is at a premium, small double's that maximise storage (such as ottoman or divan bases) are an ideal choice.

Best for: 1 person and small bedrooms

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What size is a double bed and mattress?

Measured in metric units, a standard double bed and mattress is 135cm wide and 190cm long. Converted to imperial units, this equates to 4 feet 6 inches wide and 6 feet 3 inches long. A standard double bed and mattress (4’6”) is designed to sleep two adults comfortably. This is the most common and widely available size for all bed types in the UK.

Best for: Comfortably fit 2 people and for small to average sized bedrooms

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What size is a king size bed and mattress?

Measured in metric units, a king size bed and mattress is 150cm wide and 200cm long. Converted to imperial units, a king size bed and mattress is 5 feet wide and 6 feet 6 inches long. A standard ‘King Size’ (5’0”) bed includes a longer length than the standard ‘double’ bed and mattress - 6’6” instead of 6’3”.  A king size bed will provide plenty of room for two adult sleepers, but should only be used in larger bedrooms with more space available.

Best for: 2 people wanting that extra space and those people taller than 190cm

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What size is a super king size bed and mattress?

Measuring in at 180cm wide and 200cm long or equally 6 feet wide and 6 feet 6 inches long, the super king is the largest of all standard UK sizes. The super king (6’0”) sized bed provides an abundance of space for two sleeping adults; perfect for couples who prefer their own space. Nothing beats a Sunday morning enjoying time with your family all squeezed in together (pets included too!).

Best for: 2 people for large bedrooms that value space when they sleep

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These are the standard sizes of beds and mattresses in the UK, but be sure to always double-check – just in case. Some retailers have their own bed and mattresses, which is REALLY annoying because it means you have to buy both the bed frame and the mattress from the same store, instead of being able to mix and match.

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IKEA Bed Sizes

One example of such a store is IKEA who have their own standard of beds and mattress sizes.
IKEA Bed/Mattress Size Dimensions (Imperial) Dimensions (Metric)
IKEA Single 2'6'' x 6'6'' 90 x 200cm
IKEA Double 4'7'' x 6'6'' 140 x 200cm
IKEA King Size 5'2'' x 6'6'' 160 x 200cm
IKEA Super King Size 6'0'' x 6'6'' 180 x 200cm
MyBedFrames can provide bespoke mattresses sizes to fit IKEA beds (and other custom dimensions) – call 01234 834693 for more information about this service.