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UK Mattress Sizes: Comprehensive Guide

Everything you need to know about mattress sizes, plus helpful tips on measuring up.

UK Mattress Sizes: Comprehensive Guide

When it comes to mattresses, size matters.

There are many factors to consider when choosing a mattress size, from the most popular size to the size that will work best for you. You may even be unsure of what sizes are available or exactly how big they are. If you've ever wondered which mattress is bigger, a European king or a super king, you're not alone. We've got you covered with an extensive guide to all things mattress sizes.

Throughout our lives, our bodies sleep on many different-sized mattresses, from cot-sized sleepers to super king-size designs. This mattress guide details the various sizes available to UK mattress buyers, and helps you understand which size mattress will best suit you and your needs.

How Do I Know What Size Mattress to Get?

There's a lot to think about when shopping for a new mattress, and deciding what size mattress to opt for depends a lot on personal preference. If you're sharing a bed (or sleep alone but love a good starfish!), you might want to explore larger doubles and king sized mattresses. If you're trying to save on space, small doubles or singles might be best.

This part of our mattress size guide informs you about mattress types, sizes and who they are suited for.


Small Single - Width 75cm X Length 190cm

A small single mattress is ideal for younger kids with narrow beds. As well as that, if you’re looking for something small and easy to fit into a spare room, this will do the job too. It can also be moved around easily, making it ideal for guests. 

The width of the mattress measures 75cm, which should be a natural fit for all toddlers moving up from a cot.

A small single ensures they can enjoy their first bed with a comfortable mattress that effortlessly fits into any kids’ room. And, given the small size, there will still be room for all toys!

Single - Width 90cm X Length 190cm 

The single mattress is suited for a range of people. Firstly, it’s an excellent option for kids as it’s unlikely they will grow out of it throughout their teens, meaning it’s a perfect long-term option. That also brings financial benefits as kids can grow fast, but a single mattress should still provide them with enough comfort over the years, and it measures 90cm by 190cm. 

Furthermore, it’s ideal for those who sleep independently, providing you with enough space to sleep comfortably without taking up much space in the room. They’re also popular as guest beds for the spare room, which may not be as big as the regular bedrooms.

Small Double - Width 120cm X Length 190cm

Next, we have the small double mattress, which serves many purposes again. If you’re a restless sleeper or enjoy more space, this is a better option than a single. The added space comes in width, evident by the measurements of 120cm by 190cm, and provides extra space that is needed for those of you who toss and turn.

Although, it can also be used for couples, primarily if you sleep closer together. Another reason for its popularity among couples is that it doesn’t take up much room. The small double can do the job if you don’t have space or seek a little more.

Double - Width 135cm X Length 190cm

Traditionally double mattresses, this is the number one bed for couples. Measuring 135cm by 190cm will provide sufficient room to sleep peacefully without getting on each other’s nerves at night!

Additionally, the double bed fits into standard bedrooms with ease. It’s also an excellent choice for the guest room, where a friend could enjoy the luxury of a double bed to themselves, or couples could sleep comfortably. Either way, you can’t go wrong. 

King Size - Width 150cm X Length 200cm

The king-size mattress is the one for all who want plenty of room. Even sleeping next to your partner, you should be able to roll over without disturbing them in this 150cm by 200cm mattress.

From a logical perspective, this is ideal for taller women and especially men who look to stretch out without their feet hanging out of the bed! 

The downside is that not everyone has room for a king size, preventing many people from buying it. Yet, if you do, it’s worth it. With so much space and comfort guaranteed, you’ll enjoy a king-size mattress. 

Super King Size - Width 180cm X Length 200cm 

If you thought a king-size was good, this is even better. As the name suggests, the super king size mattress is even more significant and provides much room. A 6FT mattress measures 180cm by 200cm and is the biggest available in the UK. 

You and your partner can roll over and starfish all night, although it presents the identical obvious drawback as the king size.

You may struggle to fit one of these into your room, but we’re sure you won’t regret it if you can! 

If that wasn’t enough, you could also check out our European mattresses in IKEA sizes that may appeal. Finally, you can build a custom mattress, with every detail from the length to the mattress’s width exactly how you want it, which we can then deliver.

That covers the fantastic, extensive range of mattress sizes available with Rest Relax, and as you can see, we’ve got something for everyone. Whether you’re looking for a first bed for your toddler or want to relax in a super king-size, the perfect mattress is only a click away. 

Moreover, each mattress comes in a different style, with many great options designed to give you the most comfortable night’s sleep possible.

So, what are you waiting for? We know that picking the right mattress is essential to a good night’s sleep, and you won’t go wrong with our extensive range in all sizes. 

What Size is a European Small Single Mattress?

A European single mattress size is 80cm x 200cm, or 2ft6 x 6ft6.

As well as standard small single mattresses, there is also a third variant of single mattress available - the European small single. Small Single mattresses and European small single mattresses are slightly different. Their widths are different and the European variant is longer, perfect for the taller small single sleepers amongst us. It's important to double check your bed frame when buying a European mattress, as a European mattress will be slightly too long for a standard small single bed frame.

What Size is a European Single Mattress?

A European single mattress size is 90cm x 200cm, or 3ft x 6ft6.

As well as standard single mattresses and small singles, there is also a forth variant of single mattress available - the European single. Single mattresses and European single mattresses are slightly different. While they are the same width, the European variant is longer, perfect for the taller single sleepers amongst us. It's important to double check your bed frame when buying a European mattress, as a European mattress will be slightly too long for a standard single bed frame.

European single mattresses are suitable for: European single beds.

What Size is a European Double Mattress?

A European double mattress size is 140cm x 200cm, or 4ft7 x 6ft6.

Much like their single mattress counterparts, the major difference between a double mattress and a European double mattress is the size. A European double is slightly longer, making it ideal for taller sleepers.

What Size is a European King Size Mattress?

A European king size mattress is 160cm x 200cm, or 5ft2 x 6ft6.

Like other European mattress types, European king mattresses are longer, making them perfect for tall sleepers.

How to find your perfect bed size

Accurate measurement is key if you want the right size bed and mattress. We’d recommend double-measuring everything to ensure you’ve got it right. Below, we cover a few essential sizing considerations when buying a new bed or mattress.

1. Choosing the right bed size for your body size

The most important thing when choosing between bed sizes is that you find a model that’s right for you. After all, there’s no point in having a mattress that you aren’t comfortable sleeping in! As a general rule of thumb, you want a bed that is at least 10cm longer than the height of the tallest person using it.

You also want to make sure that the mattress is wide enough. To do so, lie on your side and tuck your hands on your head, so your elbows stick out in front of your chest. If your elbows reach the edge of the mattress or touch your partner, you may want to think about a larger bed.

2. Choosing the right bed size for your room

It’s important to remember that your bed isn’t the only thing in your bedroom. That means you need to make sure there’s space for any additional furniture and for you to move around without bashing your shins on the corner of the bed! Think about how much space you need, measure it, and then work out what’s left for the bed. 

Remember to consider the way wardrobe doors open and make sure you think about the smaller details, such as where plug sockets are located and how the size and positioning of the bed will affect their use.

3. Choosing the right mattress size for your bed

While bed frames are usually designed to match up with a specific mattress size (e.g., a standard double frame for a standard double mattress), there is some variation. Design features like headboards and footboards can influence the mattress sizes you’ll be able to use, so it’s always a good idea to measure first.

Keep in mind that bed frames might be slightly larger than your mattress to allow for a perfect fit, so do look up the accurate dimensions of your bed frame to ensure it fits properly in your room. You don't want to bash your shins!

How to measure your bed

To measure your bed properly, measure from the very bottom of the bed frame to the very top - making sure you measure to the outsides of the frame. This will give you the accurate length of the bed, and you can measure from side to side from the width. It will also be worth measuring the height of your bed - from the floor to the highest point of the base - as you will need to add this to your mattress depth for the total height of the bed. 

How to measure your mattress

Using a tape measure, you should measure from top to bottom for the length of the mattress, and side to side for the width. Measure from seam to seam, as this will provide the most accurate measurement. It will be helpful for you to know the depth of your mattress, as this will help with both understanding how tall your bed will be in total, and help when purchasing fitted sheets. For mattresses over 35cm thick, you may need extra deep fitted sheets.