Your Guide To Mattress Sizes

Where you’re going to sleep is one of the most important factors when creating your perfect bedroom. But knowing what size bed and mattress you need isn’t always as simple as it sounds. Whether in an alcove or the centre of the room, against a wall or beneath a window, it’s an important to measure both your room and new bed when designing your bedroom. We’ve put together this guide on standard UK mattress sizes to help you figure out what space you have available. Though, be aware that you will also have to take the bedframe into consideration when measuring up your space.

UK Bed & Mattress Sizes

Mattress/Bed Cot Toddler Small Single Single Small Double Double King Super King
Dimensions W x L (cm) 60 x 120 70 x 140 75 x 190 90 x 190 120 x 190 135 x 190 150 x 200 180 x 200
Dimensions W x L (feet) 23" x 47" 2'3" x 4'6" 2'6" x 6'3" 3'0" x 6'3" 4'0" x 6'3 4'6" x 6'3" 5'0" x 6'6 6'0" x 6'6"


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Adult Mattress Sizes

As an adult, a mattress can be a long-term investment. If cared for properly, our mattresses should last eight years before you need to replace it. So it’s vital that you get the correct size for your bedroom.


What size is a single mattress?

Ideal for one person, a single mattress measures 90cm (3’0”) wide and 190cm (6’3”) wide. This is the smallest mattress available for an adult.

Who would suit a single bed and mattress?

A single bed and mattress are suitable for one adult only. Therefore, it is perfect for adults that sleep alone and want to save space in the bedroom. Alternatively, this size can make a great option for a guest bed, especially if you don’t often have guests and want to keep costs to a minimum. A single bed and mattress is also a great choice if you want a multifunctional spare room, such as a working office and guest bedroom all-in-one.

This size can also accommodate a child if you don’t want to go through the various bed sizes as they grow. This is a popular option for families that want the affordable option of a bed that will see their child through from toddler to teen.

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What size is a small double mattress?

Just 15cm narrower than a standard double mattress, the size of a small double mattress measures 120cm (4’0”) wide and 190cm (6’3”) long. Although these can fit two adults if necessary, we generally advise this size of mattress for just one person.

Who would suit a small double bed and mattress?

If you are short on space in your bedroom, a small double bed and mattress can be a great option. We would recommend that this bed is used by just one adult, although it can be used by two people, most would find it a bit of a squeeze. If you choose a small double divan or ottoman with your small double mattress, you can make the most of your small room, as you also have storage in your bed. If you sleep on your own, but love to have that bit of extra space like to spread out, a small double mattress will be ideal even if you have a room that would accommodate a larger bed.

This size can also make a good choice for older teenager who wants a bit of extra space when they sleep.

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What size is a double mattress?

A UK double mattress measures 135cm (4’6”) wide and 190 (3’0”) long. This makes this sized mattress our most popular, as it is ideal for couples, but doesn’t take up too much space.

Who would suit a double bed and mattress?

As already stated, this size bed and mattress is perfect for couples. If you have a average or small sized bedroom, a double bed and mattress give you enough room to sleep without taking up too much floor space.

If you want to sleep two adults in your bedroom, but have a smaller bedroom, choose a divan or ottoman double bed so that you don’t have to worry about storage furniture taking up too much space either. This is also an affordable way to get a piece of furniture with two functions.

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What size is a king size mattress?

If you have a little extra space, you may want to opt for a king size mattress and bed. A king size mattress is 150cm (5’0”) wide and 200cm (6’6”) long. It may not sound like much more space than a double, but you’ll be surprised at how much bigger it feels when you lie in a bed this size.

Who would suit a king size bed and mattress?

As king size beds and mattresses have that extra length, they are ideal for taller people. No one likes their feet hanging off the end of the bed! This size is also a good choice for couples who like to have a little extra space as they sleep, especially if there’s plenty of space available in the bedroom.

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What size is a super king mattress?

The largest of our mattresses and the ultimate in luxury, a super king size mattress measures 180cm (6’0”) wide and 200cm (6’6”) in length.

Who would suit a super king size bed and mattress?

For those that like to make a statement, a super king size is the perfect choice. If space isn’t a worry, having a bed in this size feels like the greatest luxury.

A king size bed and mattress is also a superb option for families, especially if the kids like to climb in and get snuggly with you on those lazy Sunday mornings.

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Children's mattress sizes

Whether you are upgrading your growing child to a new bed, or about to welcome your bundle of joy into the world, we can help you to find the right sized mattress for your child to sleep soundly. The following sizes are usually used for children:

What size is a cot mattress?

A UK cot mattress is 60cm (23 inches) wide and 120cm (47 inches) long, a cot mattress usually has a depth of 10cm. They are also firmer than adult mattresses, which helps development of babies.

What ages are cot mattresses best for?

Cot mattresses are, as their name suggests, used in the cot for babies. The firmness of these mattresses will keep your baby aligned so that they can grow as they need to in their sleep. When you move your newest family member to a toddler bed is best left to your judgement. However, most common is somewhere between the ages of 18 months and 3 and a half years.

We know that becoming a new parent can be expensive, so our affordable cot mattresses ensure your baby can sleep soundly and safely without costing the earth. Often, you can even move the mattress into a toddler bed to help the transition for your little one.

What size is a toddler mattress?

A little bigger than a cot mattress, a toddler mattress is 70cm (2’3”) wide and 140cm (4’6”) long. It may sound like only a small amount of extra space, but for a child this makes all the difference.

Who would suit a toddler bed and mattress?

Our toddler mattresses match perfectly with most toddler beds. This combination is perfect for children from 18 months to 3 years old, especially if your child is finding the transition from cot to bed difficult.

What size is a small single bed and mattress?

The largest of children's beds, a standard small single mattress is 75cm (2’6”) wide and 190cm (6’3”) long. These are the same length as a standard single bed, but a little narrower.

Who would suit a small single mattress?

Young children who have outgrown toddler beds would suit a small single bed and mattress.

However, although we've classed these as more of a children's mattress, if space is at a premium, they can also work well in small bedrooms or as a guest bed. The narrowness of the bed will free up 15cm of space compared to a standard single mattress, which can make all the difference if you're short on space.


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