UK Mattress Sizes Chart: Dimensions Explained
UK mattress sizes follow standard dimensions that help you choose the right fit for your bed frame, bedroom and sleeping needs. The most common sizes are small single 75x190cm (2ft6), single 90x190cm (3ft), small double 120x190cm (4ft), double 135x190cm (4ft6), king 150x200cm (5ft) and super king 180x200cm (6ft). This guide gives exact measurements, a comparison table and practical rules to avoid common mistakes when buying.
Standard UK Mattress Sizes
Every UK mattress must meet fire safety rules under the Furniture and Furnishings (Fire) (Safety) Regulations 1988 and is tested to BS 7177. Dimensions are given in both centimetres and approximate feet and inches for easy reference. Always measure your bed frame inside the rails before ordering because UK sizes differ from EU equivalents such as an EU double at 140x200cm or EU single at 90x200cm.
Width, Length and Typical Depth Ranges
Width determines how much space each sleeper has. Length is critical for taller adults; anyone over 183cm usually needs at least 200cm. Depth (thickness) affects feel and compatibility with your bed frame. Most modern frames accept 20-30cm depths, but always check the frame manufacturer’s maximum before purchase.
| Size Name | Width x Length | Common Name | Typical Use |
|---|---|---|---|
| Small Single | 75 x 190cm (2ft6 x 6ft3) | 2ft6 | Child or small guest room |
| Single | 90 x 190cm (3ft x 6ft3) | 3ft | One adult or teenager |
| Small Double | 120 x 190cm (4ft x 6ft3) | 4ft | One adult who likes extra width |
| Double | 135 x 190cm (4ft6 x 6ft3) | 4ft6 | Couples on a budget |
| King | 150 x 200cm (5ft x 6ft7) | 5ft | Most popular for couples |
| Super King | 180 x 200cm (6ft x 6ft7) | 6ft | Luxury space for two adults |
Children’s and Cot Mattress Sizes
Cot mattresses are commonly 60x120cm. Cot bed and toddler bed mattresses measure 70x140cm. When choosing bunk beds, the top bunk must comply with BS EN 747: the guard rail must rise at least 16cm above the mattress surface, so use the exact maximum mattress depth stated by the bed maker. Top bunks are not recommended for children under 6.
For growing children, a single 90x190cm mattress offers longer-term use than a cot bed size. The kids single beds category shows many frames designed exactly for the 90x190cm UK single mattress.
How to Choose the Right Mattress Size for Your Room
Measure the room and allow at least 60cm clearance on each side for making the bed and walking around. In a small bedroom a 135x190cm double mattress often fits better than a 150x200cm king. Add the height of the bed frame plus mattress depth to check ceiling clearance for bunk beds or cabin beds.
Practical checklist:
- Measure inside the bed frame rails – subtract 2cm from stated mattress width for easy fit.
- Check doorways and staircases if the mattress must be carried upstairs.
- Decide who sleeps in the bed: one person, couple, child, or guest.
- Consider future needs – a single now may become too small in two years.
- Match depth to your frame: deeper mattresses need taller side rails.
A single mattress is the most common starter size for children moving from a cot.
Mattress Depth Explained
Depth is not shown in the size name, so always read the product page. Shallower mattresses (under 20cm) suit platform beds with solid bases. Deeper ones (25-35cm) usually contain more pocket springs or layered foam for comfort. If you add a mattress topper, total depth increases, so check your frame will still contain it safely.
Pair any mattress with a good protector to extend its life. See the range of mattress protectors that fit all standard UK sizes.
Comparing UK Sizes with EU Sizes
UK single (90x190cm) is shorter than the EU single (90x200cm). UK double (135x190cm) is narrower than the EU double (140x200cm). King and super king sizes have no direct EU equivalent. Always confirm exact centimetres rather than relying on the name when ordering from mixed UK/EU suppliers.
Popular Mattress Types for Each Size
Once you know the size, choose the right construction. Memory foam, pocket sprung and hybrid options are available across all dimensions. For children, look for wipe-clean or waterproof versions. The memory foam mattresses category includes many single and double options that suit everyday use.
Recommended picks for common sizes:
The Noomi Waterproof Eco Foam Mattress Single is ideal for a child’s 90x190cm bed because the waterproof cover handles spills and the foam depth fits most single frames.
The Maxitex Kids Premier Sprung Mattress suits the small double or single size and gives firm support that lasts through the growing years.
The Maxitex Diamond Dual Season 1000 Pocket Memory Mattress in double size offers two comfort feels in one 135x190cm mattress, useful when partners prefer different firmness.
The Noomi Bamboo Natural Latex Pocket Sprung Mattress in king size provides natural temperature regulation across the wider 150x200cm surface.
Final Decision Rules
Write down your room measurements, the people who will use the bed, and the maximum depth your frame allows. Cross-check against the chart above. Order the exact size name only after confirming the centimetres on the product page. Add a mattress topper from the mattress toppers range if you need extra cushioning without changing the base mattress size.
Our picks for this guide
- Noomi Waterproof Eco Foam Mattress Single – Fits the standard UK single 90x190cm size and the waterproof cover makes it practical for children or guest rooms.
- Maxitex Kids Premier Sprung Mattress – Designed for the UK single or small double size with firm sprung support suitable for growing children.
- Maxitex Diamond Dual Season 1000 Pocket Memory Mattress – Available in double size and offers two firmness options in one 135x190cm mattress for couples with different preferences.
- Noomi Bamboo Natural Latex Pocket Sprung Mattress – Suits the UK king 150x200cm size with natural materials that help regulate temperature across the wider sleeping surface.
Frequently asked questions
What is the difference between a UK double and a small double mattress?
A UK small double measures 120x190cm (4ft) while a standard double is 135x190cm (4ft6). The extra 15cm width gives each person more space in the larger size. Choose 4ft if the bedroom is tight; otherwise the 4ft6 offers better long-term comfort for couples.
Can I use a European size mattress on a UK bed frame?
Usually no. A UK king is 150x200cm while many EU kings are 160x200cm. The length difference of 10cm on singles and doubles also causes overhang or gaps. Always match the exact centimetre measurements rather than the name.
What size mattress fits most bunk beds?
Most UK bunk beds are built for the standard single 90x190cm mattress. Check the manufacturer’s stated maximum depth so the top bunk guard rail still rises 16cm above the mattress. Never exceed that depth.
How do I know what depth mattress to buy?
Measure the internal height of your bed frame sides. Subtract at least 2cm to avoid the mattress sitting proud. Most frames accept 20-30cm depths. Deeper mattresses usually need taller frames or divan bases.
Is a super king mattress worth the extra space?
A super king 180x200cm gives each adult 90cm of width compared with 75cm on a king. It needs a larger bedroom and wider sheets. Ideal if you have the room and want maximum comfort; otherwise a standard king is sufficient for most couples.
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