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Mattress Size Guide

Mattress Size Guide

When it comes to mattresses, size matters.

There is a lot to take into consideration, from what mattress size is the most popular to which size will work best for you. You might even be unsure of what sizes are available or exactly how big they are. If you've found yourself wondering which mattress is the biggest, European king or super king, don't stress - we've got you covered with an extensive guide to all things mattress sizes.

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

Mattress sizes

See below for the measurements of Happy Beds' mattress sizes:

mattress sizes

Cot Mattress Size

60cm x 120cm / 2ft x 3ft9

Toddler Bed Mattress Size

70cm x 140cm / 2ft3 x 4ft6

Small Single

72cm x 190cm / 2ft6 x 6ft3

Single Mattress Size

90cm x 190cm / 3ft x 6ft3

European Single Mattress Size

90cm x 200cm / 3ft x 6ft6

Small Double Mattress Size

120cm x 190cm / 4ft x 6ft3

Double Mattress Size

135cm x 190cm / 4ft6 x 6ft3

European Double Mattress Size

140cm x 200cm / 4ft7 x 6ft6

King Size

150cm x 200cm / 5ft x 6ft6

European King Mattress Size

160cm x 200cm / 5ft2 x 6ft6

Super King Mattress Size

180cm x 200cm / 6ft x 6ft6

Please note, all sizes are approximates and all products do have a tolerance of up to 2 inches.

Which mattress size suits me?

Throughout our lifetime, our bodies sleep on many dozens of different-sized mattresses, from cot-sized sleepers to super king-size designs. This part of our mattress size guide informs you about mattress types, sizes and who they are suited for.

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.

What size are cot and toddler mattresses?

A standard cot mattress size is 60cm x 120cm, or 2ft x 3ft9, while a toddler mattress is 70cm x 140cm, or 2ft3 x 4ft6.

The most important aspect of cot mattresses and toddler mattresses is the safety of the little person sleeping on them. However, every child also needs a comfortable night's sleep and ample room to accommodate their growth.

The best cot and toddler mattresses offer plenty of space for your child as they grow, while prioritising safety and comfort.

It's important to note that transitioning your child from a cot to a toddler bed can often be awkward, so for more information about what you can do to make the move easier, take a look at our transitioning guide.

What size is a small single mattress?

A small single mattress is 72cm x 190cm, or 2ft6 x 6ft3.

If you're looking for a comfy, snug sleep for smaller people, a small single mattress is a great option. These mattresses are ideal for children, as they leave enough excess to accommodate further growth.

Small single mattresses are ideal when paired with a bunk bed, too, perfect for families with two or more children. For more information, take a look at the pros and cons of bunk beds.

Small single mattresses are suitable for: small single beds and bunk beds.

What size is a single mattress?

The dimensions of a standard single mattress are 90cm x 190cm, or 3ft x 6ft3.

Single mattresses are perfect for teenagers and those with little space in their bedroom or spare room. Our range of single mattresses has enough variations to ensure that our customers can sleep on the right type of mattress, even if it's on the smaller side.

Increasingly, more couples are choosing to use two single mattresses instead of a larger mattress.

Standard single mattresses are suitable for: single beds.

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 third 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 small double mattress?

A small double mattress is 120cm x 190cm, or 4ft x 6ft3.

As evidenced by the name, a small double mattress is slightly smaller than its counterparts, making it ideal for one person or a couple with a smaller bedroom.

Having a small double mattress, especially when combined with a divan or storage bed, opens up new avenues to save space in your bedroom.

Small double mattresses are suitable for: small double beds, divan beds and storage beds.

What size is a double mattress?

The measurements of a double mattress are 135cm x 190cm, or 4ft6 x 6ft3.

When you're sleeping alongside someone else - as a huge percentage of people do - it's essential to sleep on a mattress that's big enough for the two of you. For that, you need a double mattress at least, although most will opt for a king or super king size.

Double mattresses are suitable for: double 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 king size mattress?

A king size mattress dimensions are 150cm x 200cm, or 5ft x 6ft6.

Alongside double mattresses, king size mattresses are among the most popular beds for adults, particularly if you need a little more room or like to 'sprawl' in bed. If you or your partner loves having a lot of space under the covers, then you cannot go wrong with the king size mattress.

King size mattresses are suitable for: king size beds.

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 big is a super king-size mattress?

We're often asked, "what's the largest mattress size?". At Happy Beds, our largest mattress size is the super king. A super king size mattress is 180cm x 200cm, or 6ft x 6ft6.

When you are an adult, the world is your oyster when it comes to the size of your bed. Most people opt for a double or king size mattress, but others only settle for the best: the super king size mattress.

Here, mattress size truly comes down to taste - and how much space you have in your bedroom. While the double mattress is the norm, a super king size is reserved for those who just love having oceans of space to sleep in.

Super king mattresses are suitable for: super king size beds.

Mattress sizes and bed frames

We've detailed above which bed frames fit best with each individual mattress, but we'd always recommend double checking your bed frame size when buying a new mattress, or vice versa.

This is particularly important when looking at European mattresses. As they're often the same width as their standard counterparts, people can confuse the two and think a European mattress will fit on a standard bed - only to get it home and find it's too long to fit comfortably.

Some bed frames may also have designs that make them more or less flexible when it comes to mattress size, for example, if they have a headboard or footboard. If you're unsure what size bed frame you have, you can't go wrong by getting out the good old fashioned tape measure and confirming the measurements before you commit to your new mattress.

What mattress size is best for couples?

If you're a couple, you need to make sure your bed will comfortably fit both of you. While a double can fit two people, if you tend to sleep spread out or value your personal space while sleeping, you may find it a little bit of a squeeze. Of course, if you like to fall asleep cuddling or are prioritising space-saving, a double mattress could work perfectly for you.

However, for couples who want plenty of room, we'd recommend looking at king size mattresses or bigger. The super king is our biggest size available and is ideal for those who want lots of wriggle room when catching their forty winks.

What mattress size is best for single sleepers?

When looking at the best mattress sizes for single sleepers, a lot depends on the preferences of the sleeper. A standard single works perfectly if you don't move a lot in the night or are trying to save space in a smaller bedroom. For a little more room, a small double means you can stretch out a bit more while still offering a space-saving option.

If space in your room isn't an issue, the world is your oyster! You can choose a double or a king and enjoy having all the stretching room you could dream of.

How to choose your mattress size

There are also other steps that you can take to ensure you're buying the right mattress for your needs and lifestyle:

  • Measure yourself - try to ensure that the mattress is 15cm longer than the tallest person who will sleep on the mattress.
  • Stretch - if you can place your hands behind your head and your elbows touch the mattress edge or your sleeping partner, your mattress isn't big enough for you.
  • Scope out your room - it's all well and good having a huge mattress to sleep in, but if it doesn't suit your bedroom or seriously limits your space, it may be worth investing in something slightly smaller. Measure out, make sure there's enough room.
  • Consider your sleeping position - as well as your height, you should think about your sleeping position when deciding what size mattress you need. If you sleep on your back or your front you will be sleeping fully extended, so may require more legroom. If you tend to sleep on your side with your legs tucked in, a smaller mattress may suffice.
  • Check your bed - it should go without saying, but you should check that the mattress you're buying matches the dimensions of your bed frame. You can see the dimensions of all our bed sizes detailed above, so make sure you've double checked the size of your bed to ensure your new mattress is a perfect fit.
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I think the whole thing went perfectly…
I think the whole thing went perfectly…
I think the whole thing went perfectly from start t finis
Very good
Very good
Brilliant material, easy assembly, very nice service
Excellent customer service!!
Excellent customer service!!
Kyi from Happy Beds was excellent in sorting a problem out. Amazing customer service!. Thank you!! Mr Edwards
Fantastic mattress
Fantastic mattress
Fantastic mattress, very comfortable
Really good customer service from…
Really good customer service from…
Really good customer service from Chantal. She was very professional and dealt with my query very efficiently and quickly.
Great thanks
Great thanks
First class service throughout from Happy Beds. Thank you very much. Mattress delivered earlier than expected. Delivery guys very friendly and professional. They found the marina very easy. I went to them after phone call, to say they had arrived. Helped me load mattress on a trolley, waved bye. Mattress looks great and fits perfect. Highly recommend Happy Beds.
Great company even better customer service
Great company even better customer service
Quick delivery, good quality items. Customer service is great, we were speaking to a lady called Aimee as one of the parts for the bed was faulty. Dealt with it quickly and replacement sent a couple days after the initial enquiry. Thank you
Great prices and even better customer…
Great prices and even better customer…
Great prices and even better customer service. really impressed with this company. bunk beds are great and the problem I had was resolved by Caroline and Sophie with no hassle. Would definitely buy from them again