Choosing the right bed size can make or break your sleep — and your bedroom. Too small and you're cramped all night. Too big and you can barely move around the room. Get it right, and you'll wonder why you didn't sort it sooner.
Whether you're upgrading from a single to a double, debating king vs super king, or just trying to work out if that emperor-sized dream will actually fit through your door — this guide covers everything you need to know about UK bed sizes, room measurements, and how to pick the perfect fit for your space.
UK Standard Bed Sizes: The Complete Table
First things first — here are the standard UK bed sizes. These are the dimensions you'll find across British bed retailers, including us here at Britain Sleep. Keep in mind that the measurements below refer to the mattress size. Your bed frame will typically add 5-10 cm on each side.
| Bed Size | Width | Length | Metric (cm) | Best For |
|---|---|---|---|---|
| Small Single | 2'6" | 6'3" | 75 × 190 | Children, very small rooms |
| Single | 3'0" | 6'3" | 90 × 190 | Children, teenagers, guest rooms |
| Small Double (4ft) | 4'0" | 6'3" | 120 × 190 | One person wanting extra space, compact rooms |
| Double | 4'6" | 6'3" | 135 × 190 | Couples in standard bedrooms |
| King | 5'0" | 6'6" | 150 × 200 | Couples wanting more room, taller sleepers |
| Super King | 6'0" | 6'6" | 180 × 200 | Couples who want maximum space, larger bedrooms |
Important: UK bed sizes are different from US and European sizes. A UK king (150 × 200 cm) is not the same as a US king (193 × 203 cm). Always check you're buying to UK dimensions if your mattress is UK-standard.
Room Size Calculator: What Fits Where?
Your dream bed is only a good choice if it actually fits your room — with space to walk around, open wardrobe doors, and not feel like you're sleeping in a cupboard. There's nothing worse than squeezing past a bed frame every morning.
Here are the minimum room dimensions we recommend for each bed size, allowing for at least 60 cm (2 feet) of walking space on each side and at the foot of the bed:
| Bed Size | Minimum Room Width | Minimum Room Length | Comfortable Room Size |
|---|---|---|---|
| Single (3'0") | 2.1 m (7'0") | 2.7 m (9'0") | 7 m² (75 sq ft) |
| Small Double (4'0") | 2.4 m (8'0") | 2.7 m (9'0") | 8 m² (86 sq ft) |
| Double (4'6") | 2.6 m (8'6") | 2.7 m (9'0") | 9.5 m² (102 sq ft) |
| King (5'0") | 2.7 m (9'0") | 3.2 m (10'6") | 12 m² (129 sq ft) |
| Super King (6'0") | 3.0 m (10'0") | 3.2 m (10'6") | 14 m² (150 sq ft) |
Top tip: Measure your room before you fall in love with a bed. Use painter's tape on the floor to mark out the bed footprint — it's the fastest way to see if the size works. Don't forget to measure doorways and staircases too. Most of our beds arrive flat-packed for easy assembly, but it's always worth checking.
How to Choose the Right Bed Size
For Couples
If you share a bed, a double (4'6") is the minimum — but it's tighter than you think. Each person gets just 2'3" of width, which is actually narrower than a standard single bed. If you value your sleep (and your relationship), a king (5'0") is where real comfort starts for two people.
Super king gives you proper luxury — 3 feet each, plus room for a pet, a child who climbs in at 3am, or simply the freedom to stretch out without elbowing your partner. If your room can handle it, you won't regret going bigger. Your sleep quality will thank you.
For Taller Sleepers
Standard UK beds (single, small double, double) are 6'3" (190 cm) long. If you're over 6 feet tall, your feet may hang off the end — not ideal in the middle of winter. A king or super king adds an extra 3 inches in length (200 cm), which makes a genuine difference to how comfortably you sleep.
At Britain Sleep, we can also build beds to custom lengths if you need something outside standard dimensions. That's the real advantage of made-to-order — your bed fits you, not the other way around.
For Small Rooms
Small bedrooms don't mean you have to settle for a small bed. The trick is choosing a bed that works harder — one that does double duty. An ottoman bed gives you the entire base as storage space, removing the need for bulky chests of drawers or under-bed boxes.
An ottoman double in a 9 m² room gives you a proper-sized bed plus more storage than a wardrobe — without taking up any extra floor space. That's smart design, not compromise. You keep the bed size you need and gain storage you didn't know you had.
For Children and Teenagers
A single (3'0") works perfectly for young children up to about age 10-12. As they hit their teens and start growing, consider a small double (4'0") — it gives growing bodies more room without dominating the bedroom. It also means they can comfortably have a friend stay over without needing a separate guest bed.
For Guest Rooms
A double (4'6") is the sweet spot for most guest rooms. It comfortably accommodates a couple for a few nights without requiring a huge room. If space is tight, a small double (4'0") still feels generous for a single guest. Pair it with an ottoman base and you've got storage for spare bedding right under the mattress.
Ottoman Beds: The Smart Choice for Any Room Size
If you're battling with space — and let's be honest, most of us are — an ottoman bed deserves a serious look. The entire base lifts up on heavy-duty gas-lift struts to reveal a massive storage cavity underneath. We're talking enough room for duvets, pillows, seasonal clothes, shoes, luggage — all hidden away neatly under your mattress.
Unlike divan drawers that need clearance space to open, an ottoman's lift-up mechanism works in any room layout. Even if your bed is pushed against a wall, you can still access everything inside. That's a game-changer for box rooms and awkward layouts.
Browse our full ottoman bed collection — over 120 designs in 200+ fabrics, from plush velvets to natural linens. Every one is handcrafted in our West Yorkshire workshop and delivered free across the UK mainland.
Every Size, Built to Your Exact Specification
At Britain Sleep, we make every bed to order — from Single right through to Super King. But we don't stop at standard sizes. Need a non-standard width? A longer length for a taller sleeper? A specific headboard height to match your bedroom? We build it.
Your bedroom, your colour. Choose from 200+ fabrics — crushed velvets, plush chenilles, smooth linens, and more. Pick your size, choose your storage option, select your headboard style, and we'll handcraft it in our Dewsbury workshop. Free UK mainland delivery is included on every order.
Explore our full bed collection to find your perfect fit.
Frequently Asked Questions
What is the most popular bed size in the UK?
The double (4'6" × 6'3") remains the most popular bed size in the UK. However, king size beds are growing in popularity as people prioritise sleep quality and new-build homes tend to have larger master bedrooms.
Is a king size bed worth it?
If your room can fit a king comfortably (you need at least 12 m²), then absolutely. The extra 6 inches of width over a double makes a noticeable difference for couples — each person gets 2'6" instead of 2'3". It also adds 3 inches of length, which matters if either of you is taller than 5'10".
What's the difference between UK and US bed sizes?
UK and US sizes share the same names but have different dimensions. A UK king is 150 × 200 cm, while a US king is 193 × 203 cm — that's closer to a UK super king. If you're buying a mattress online, always check which sizing standard is being used.
Can I get a custom size bed from Britain Sleep?
Yes — because we build every bed to order, custom sizes are straightforward for us. Whether you need an extra-long single for a tall teenager, a narrower double to fit an alcove, or a non-standard headboard height, we can make it. Browse our collections and get in touch to discuss your requirements.
How much space should I leave around my bed?
We recommend at least 60 cm (2 feet) on each side you need to walk past, and the same at the foot of the bed. If you have bedside tables, factor those in too — most are 40-50 cm wide. Don't forget about wardrobe doors and drawers that need room to open.
Do ottoman beds come in all sizes?
Yes. Our ottoman beds are available in Single, Small Double, Double, King, and Super King sizes. Every size features the same heavy-duty gas-lift mechanism for easy, one-handed access to the full storage cavity underneath.