Children's Bed Size Guide – UK & European Bed Sizes Explained
Choosing the right bed size for a child isn't always straightforward. Children's beds are available in several different sizes, and some children's furniture uses UK mattress sizes while others use European or continental sizes.
The difference can be particularly important when buying a bunk bed, cabin bed, mid sleeper or high sleeper, as the mattress needs to fit the bed correctly.
In this guide, we explain the most common children's bed sizes and mattress sizes, the difference between UK and European single beds, and what to consider when choosing a bed that your child can grow into.
Children's Bed Sizes at a Glance
The most common children's bed and mattress sizes you'll come across include:
| Bed Size | Typical Mattress Size | Suitable For |
|---|---|---|
| Toddler bed | Varies | Toddlers and young children |
| UK Single | 90 × 190cm | Children, teenagers and adults |
| European Single | 90 × 200cm | Children, teenagers and adults |
| Small Double | 120 × 190cm | Older children and teenagers |
| Double | 135 × 190cm | Teenagers and adults |
| European Double | 140 × 200cm | Older children, teenagers and adults |
Always check the individual product specifications before buying a mattress, as bed dimensions can vary between manufacturers.
What Is the Standard Children's Bed Size?
There isn't one single standard size for children's beds.
The UK single bed, measuring approximately 90 × 190cm, is one of the most common sizes used for children's bedrooms.
However, many children's beds imported from European manufacturers use a 90 × 200cm continental single mattress instead.
This extra 10cm of length can make a significant difference when buying a replacement mattress, so it's important to check which size your bed requires.
UK Single Bed Size – 90 × 190cm
A standard UK single mattress measures:
90cm wide × 190cm long
This is commonly referred to as a 3ft single bed.
It is a versatile size that can be used by:
- Young children
- Older children
- Teenagers
- Adults
One of the advantages of a standard single bed is that it can remain suitable for a child for many years.
A UK single mattress is also widely available, making replacement mattresses and bedding relatively easy to find.
European Single Bed Size – 90 × 200cm
A European or continental single mattress is typically:
90cm wide × 200cm long
It has the same width as a UK single but is 10cm longer.
This size is particularly common in children's beds manufactured by European furniture companies.
The additional length can be useful as children grow, particularly for teenagers and taller children.
However, a 90 × 200cm mattress cannot simply be substituted for a 90 × 190cm mattress. The mattress must match the dimensions specified by the bed manufacturer.
UK Single vs European Single
The difference is easy to remember:
UK Single: 90 × 190cm
European Single: 90 × 200cm
Both are approximately 90cm wide, but the European mattress is 10cm longer.
This is particularly important when buying children's beds from European manufacturers.
At Family Window, you'll find children's beds using both UK and European mattress sizes, so always check the individual product description before ordering.
Why Do Some Children's Beds Use European Mattress Sizes?
Many children's furniture brands sold in the UK are manufactured in continental Europe.
European furniture commonly uses different mattress dimensions from traditional UK beds.
As a result, you may find a beautiful children's bed that requires a 90 × 200cm mattress rather than the more familiar 90 × 190cm UK single.
This isn't a problem, but it is something you need to know before purchasing the bed.
It is also important when buying:
- Mattresses
- Mattress protectors
- Fitted sheets
- Bedding
Make sure accessories are designed for the correct mattress dimensions. Our Children's Mattress Buying Guide covers how to choose the right mattress once you know your bed's required size.
Toddler Bed Sizes
Toddler beds are generally smaller than full-size single beds and are designed as a transition between a cot and a larger child's bed.
There isn't one universal toddler bed size, so dimensions can vary between manufacturers.
Some toddler beds use mattresses around 70 × 140cm, while other designs may use different dimensions.
If you're buying a toddler bed, always check the required mattress size rather than assuming it will be a particular standard.
For younger children moving from a cot, a toddler bed can provide a more manageable sleeping environment before progressing to a full-size bed.
Small Double Bed Size – 120 × 190cm
A small double mattress is generally:
120cm wide × 190cm long
It is sometimes known as a 4ft bed.
A small double can be an interesting option for an older child or teenager who needs more sleeping space but where a standard double would take up too much room.
It can also work well in larger children's bedrooms or guest rooms.
However, small double children's beds are less common than standard single beds, so check the available furniture and mattress options carefully.
Double Bed Size – 135 × 190cm
A standard UK double mattress measures:
135cm wide × 190cm long
A double bed can be suitable for older teenagers who want more space, particularly where the bedroom is large enough to accommodate it.
It can also be a practical choice if you want the bed to remain suitable into adulthood.
However, a double bed takes considerably more floor space than a single, so consider the size and layout of the bedroom before choosing one.
Children's Bed Sizes and Growing Children
One of the biggest questions parents ask is whether they should buy a smaller bed now or choose a larger bed that will last longer.
For many children, a standard single bed can be a sensible long-term option.
A 90 × 190cm UK single can accommodate a child from their early years through to their teenage years and beyond.
A 90 × 200cm European single offers an additional 10cm of length, which can be particularly useful for taller children.
The best choice will depend on:
- Your child's age
- Their height
- Bedroom size
- Available space
- The type of bed
- Your budget
- How long you want the bed to last
What Size Mattress Does a Bunk Bed Need?
Bunk beds commonly use single mattresses, but the required size can vary.
For example, a bunk bed might require:
90 × 190cm UK single
or:
90 × 200cm European single
Don't assume that every bunk bed uses a standard UK single mattress.
You should always check the manufacturer's specifications before ordering a mattress.
This is particularly important with bunk beds because the maximum mattress depth may also be specified. Our Bunk Bed Buying Guide has more detail on choosing the right bunk bed.
What Size Mattress Does a Mid Sleeper Need?
Mid sleepers commonly use either UK or European single mattresses.
Typical sizes include:
90 × 190cm
or:
90 × 200cm
The correct size depends on the particular bed.
This is why it is important to check the product specifications rather than simply searching for a "single mattress".
If you're considering a mid sleeper, our Mid Sleeper Buying Guide explains the different designs and features to consider.
What Size Mattress Does a High Sleeper Need?
High sleepers also commonly use single mattresses.
Depending on the manufacturer, the bed could require:
- 90 × 190cm UK single
- 90 × 200cm European single
As with mid sleepers and bunk beds, the maximum mattress depth can be particularly important because of the safety rails surrounding the sleeping area.
Always follow the mattress specifications supplied with the bed.
Our High Sleeper Buying Guide provides more information about choosing a high sleeper for children and teenagers.
What Size Mattress Does a Cabin Bed Need?
Cabin beds can use a range of mattress sizes depending on their design.
Many children's cabin beds use either:
90 × 190cm
or:
90 × 200cm
European cabin beds are particularly likely to use the longer continental single size.
If you're considering a cabin bed, don't forget to check both the mattress dimensions and maximum mattress height.
Our Cabin Bed Buying Guide explains what to look for when choosing a cabin bed, including storage, desks and other features.
Bed Size Isn't the Same as Overall Bed Size
One important point to remember is that mattress size and bed size are not necessarily the same.
For example, a bed designed for a 90 × 190cm mattress may be considerably longer and wider once you include:
- Headboards
- Footboards
- Side panels
- Ladders
- Storage
- Desks
- Shelving
This is especially important with children's cabin beds, bunk beds, mid sleepers and high sleepers.
Always check the overall dimensions of the bed, not just the mattress size.
How Much Bedroom Space Does a Child's Bed Need?
When measuring for a new bed, don't simply check whether the bed itself fits.
You also need enough space to use it. Consider:
Drawers
If the bed has storage drawers, make sure there is enough room for them to open fully.
Desk
If the bed has a pull-out or integrated desk, allow sufficient space to use it comfortably.
Ladder
For bunk beds, mid sleepers and high sleepers, make sure there is clear access to the ladder.
Wardrobe
If the bed incorporates a wardrobe, allow enough space for doors to open.
Trundle or Sleepover Bed
If the bed has a pull-out guest bed, measure the additional floor space required when it is fully extended.
What Mattress Depth Should You Choose?
Mattress depth is particularly important with children's raised beds.
Bunk beds, mid sleepers and high sleepers may have a specified maximum mattress depth to ensure the safety rail remains at the required height above the mattress.
Never choose a mattress based solely on its length and width. Check:
Length + width + maximum permitted mattress depth
before buying.
Which Bed Size Is Best for a Child?
For many children, a standard single is the most practical long-term choice.
UK Single – 90 × 190cm
A good all-round choice for:
- Children
- Teenagers
- Smaller bedrooms
- Guest rooms
European Single – 90 × 200cm
A good option where:
- The bed is designed for a continental mattress
- Your child is tall or growing quickly
- You want additional length
Small Double – 120 × 190cm
Worth considering for:
- Older children
- Teenagers
- Larger bedrooms
Double – 135 × 190cm
Can work well for:
- Older teenagers
- Larger bedrooms
- Those wanting a bed suitable into adulthood
Ultimately, the best bed size is the one that fits both your child's needs and the available bedroom space.
Children's Bed Size Buying Checklist
Before ordering a new children's bed, check:
- What mattress size does the bed require?
- Is it a UK or European mattress size?
- What is the overall size of the bed?
- What is the maximum mattress depth?
- Is there enough room around the bed?
- Will drawers open fully?
- Is there enough space for a desk?
- Can the ladder be accessed easily?
- Is there enough room for a pull-out guest bed?
- Will the bed still be suitable as your child grows?
- Can you easily buy suitable bedding and accessories?
UK & European Children's Bed Size Comparison
| Mattress Size | Dimensions | Common Use |
|---|---|---|
| Toddler | Varies | Toddler beds |
| UK Single | 90 × 190cm | Children's beds, bunk beds, mid sleepers |
| European Single | 90 × 200cm | European children's beds, bunk beds, mid sleepers |
| Small Double | 120 × 190cm | Older children and teenagers |
| UK Double | 135 × 190cm | Teenagers and adults |
| European Double | 140 × 200cm | Older children, teenagers and adults |
Dimensions shown are typical mattress sizes. Always check the individual bed manufacturer's specifications.
Final Thoughts
Choosing the right size bed is about more than simply finding one that fits your child's mattress.
You need to consider the size of the bedroom, the overall dimensions of the bed, available floor space and how your child is likely to use the bed as they grow.
For many families, a UK single measuring 90 × 190cm is a versatile choice. However, if you're buying a European children's bed, you may need a 90 × 200cm continental single mattress instead.
This distinction is particularly important when buying children's bunk beds, cabin beds, mid sleepers and high sleepers.
If you're still deciding which type of bed is right for your child, explore our Buying Guides & Advice Centre for more information on choosing children's beds and bedroom furniture.