When choosing your perfect mattress, size really does matter.

We’re guessing, if you’ve landed on this page, you’ll have questions such as; what is the exact size of a King size mattress? What is the perfect size bed for a guest room? Or what size mattress will I need for my passed-down antique bedframe? We hope you’ll find the answers below, so please be our guest and read on…

When shopping for a new mattress, there is a lot to consider, and deciding what size mattress to buy is highly subjective and individual. Will you be sharing this bed with a partner? On a weekend do your kids, dog, cat, hamster or goldfish join you for a Sunday snuggle? Or do you sleep alone only to do the full Torvil and Dean Bolero routine in your sleep nightly? If the answer is yes, then you should be looking at a larger size, we’d suggest a King or above.

However, if you are limited on space, sleep like a vampire or are on a budget, maybe a double mattress or single mattress would suit you best.

What are the UK Bed Sizes?

In the UK, the standard sizes of mattresses are as follows: Small Single, Single, Small Double, Double, King and Super King. You may also find some retailers offer the sizes: Petite Double and Small Super King, as well as European sizes; Euro Single, Euro Double and Euro King. In the UK, we still tend to hark back to imperial sizes when it comes to mattress measurements, so please find the sizes written in both imperial (feet and inches) as well as metric (centimetres) below. Please note: the metric measurements are not exact, as manufacturers use imperial sizes as standard.

Mattress Sizes

See below the measurements of different mattresses that are widely available:



Please note that all measurements are approxiate.

Please note that all sizes are approximate.

Which mattress size is right for me?

Small Single Mattress size 2’6 x 6’3 or 75cm x 190cm
A Small Single size mattress is the perfect size for a small child - a great entry size for a toddler, after graduating from a Cot bed. Being 6 inches (15 cm) narrower in width makes it a great space-saving size. With this mattress being a standard length, a slender adult could easily spend a few occasional nights sleeping on this size bed, but we wouldn’t recommend it for every night use.

Small Single Mattresses are suitable for: Small Single Bed Frames.

Single Size Mattress 3’ x 6’3 or 90cm x 190cm
Perfect for a child, teenager or adult, a Single size mattress should allow ample room to sleep and be comfortable without feeling like you’re going to fall out of bed. A Single mattress is the most popular size for children as well as teenagers, also a great choice for a guest room used occasionally by adults.

Single Size Mattresses are suitable for: Single Bed Frames.

Small Double Size Mattress 4’ x 6’3 or 120cm x 190cm
A Small Double size mattress is a great size bed, perfect for smaller rooms and especially for single sleepers wanting a little room to roll around. We find this size is a great size for the growing teenager or a small guest room, allowing your guests to have a bit of room to move around, with its extra foot of space on a single bed.

Small Double Mattresses are suitable for: Small Double Bed Frames, Small Double Divan Beds and Ottoman Storage Beds.

Double 4’6 x 6’3 or 135cm x 190cm
A Double size mattress is a very popular size, it’s perfect for two adults, a great guest bed, a main bed or the ideal size for a very lucky teenager. Being a popular size, you shouldn’t have any issue finding bedding for this size mattress. If your kids join you in bed at the weekends, it may be a little snug, so we’d recommend upgrading to a King.

Double mattresses are suitable for: Double Bed Frames and Double Size Divan Beds.

King 5’ x 6’6 or 150cm x 200cm
A King size mattress is the most popular bed size in the UK, the majority of couples will sleep in a King size bed. You’ll notice that the length of the bed has increased by 3 inches (10cm) from 6’3 to 6’6 (190cm to 200cm). This extra length ensures that even the tallest amongst us can have a comfortable nights’ sleep. As mentioned previously, this size bed allows ample space for a child or even your furry friends to join you and your partner for the night.

King size mattresses are suitable for: King Size Bed Frames and King Size Divan Beds.

Super King 6’ x 6’6 or 180cm x 200cm
Big family? Like to starfish in your sleep? Then a Super King size mattress is the size mattress you need! Offering you 6 feet (180cm) of width, this is plenty of space for you and your partner plus the addition of the kids, dogs and cats who will inevitably want to join you on a Sunday morning. With the Super King being a very large size, we do ask customers to ensure access up to the bedroom is viable as well as having enough space in the bedroom itself. Please note most pocket sprung mattresses do not bend so any tight corners or shallow stairs could cause an issue.

Super King Mattresses are suitable for: Super King Size Bed Frames and Super King Size Divan Beds.

Things to consider when buying a mattress

* Size and space - It’s all well and good ordering a big mattress, but please ensure you have enough space for access (stairs, corridors and doors), as well as enough space in the intended room.

* Measure your height - Ensure that your mattress is at least 10cm longer than the tallest person who will be using the mattress, this will ensure a comfortable night's sleep for all.

* Stretch out - When putting your hands under your head, your elbows shouldn’t be able to reach the end of the mattress or touch your partner. If they do, it’s probably time to look for a larger mattress.

* Measure the internal space of your bedframe - If you’re purchasing a new mattress to go onto an existing bed frame, make sure that you measure the internal space. It is normal for the space to be a few centimetres larger than the mattress; we call this a finger gap. So, if the internal space measures 145cm x 200cm, the size you’ll need is a double, allowing 10cm extra for width and length or 5cm each side and end.

We hope you’ve found the information in our mattress size guide helpful! If you require any further information, please contact one of our knowledgeable Sales Associates on 01642 686365 or take a look at our other Mattress Buyer's Guides to help you make the right mattress choice.

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