Double vs King Size Bed: Which Is Right for You?

Choosing between a double and a king size bed is one of the most common bedroom dilemmas in UK homes, and it comes down to three things: how much sleeping space you genuinely need, how much floor space your room can spare, and what you’re comfortable spending on the frame, mattress and bedding. By the end of this guide you’ll know the exact UK dimensions of each size, how they feel to sleep on, whether your room can take a king without feeling cramped, and which choice suits your household best.

1. Double vs king at a glance

A standard UK double bed measures 135cm wide by 190cm long, while a UK king size bed measures 150cm wide by 200cm long. That’s an extra 15cm of width and 10cm of length on a king, which sounds modest on paper but changes the feel of the bed considerably, especially for two adults. The double remains the default choice for the majority of British bedrooms because it balances a comfortable sleep with a footprint that fits most rooms. The king is the upgrade you reach for when you want more shoulder room, more legroom, or simply a more generous, hotel-like sleeping space.

Neither size is universally “better.” The right answer depends on who’s sleeping in the bed, how big the room is, and how the numbers stack up once you add the mattress and bedding. Browse the full range of double beds and king size beds to see how each looks in real frame styles before you decide.

2. UK bed sizes explained

Getting the measurements right matters, because bed and mattress sizes in the UK differ from European and US standards. If you buy a frame in one size and bedding in another, nothing fits. The table below sets out the standard UK sizes so you can compare a double and king directly, with the smaller and larger neighbours for context.

The two figures that matter most in the double-versus-king decision are width and length. On a double, each person gets roughly 67cm of personal width, which is a little narrower than a single bed each. On a king, that rises to 75cm each, a full single’s worth per person. The king’s 200cm length is also a genuine benefit for anyone over about 6ft, whose feet can hang off a 190cm double. For a complete breakdown of every size, see our dedicated UK bed sizes guide.

3. Comfort and sleep quality

Couples tend to sleep better with more space, because you’re less likely to be disturbed by a partner turning over or getting up in the night. The extra 15cm of width on a king translates into noticeably less “elbow negotiation,” which is why so many people who upgrade say they’d never go back.

That said, a double is perfectly comfortable for many couples, particularly if you tend to sleep close together or one partner is slighter in build. The comfort difference is most pronounced if:

• One or both of you are tall, broad, or restless sleepers.
• You share the bed with children or pets who creep in during the night.
• You’re a light sleeper easily woken by movement.
• You like to starfish, sprawl, or sleep with plenty of duvet around you.

If any of those describe you, the king usually pays for itself in better rest. If you sleep still, cuddle up, or sleep solo, a double may serve you just as well.

4. Will it fit your room?

Bed size is only half the equation, the room has to accommodate it comfortably. As a rule of thumb, aim to leave at least 60–70cm of clear floor space along at least one side and the foot of the bed so you can walk around, make the bed and open wardrobe doors without a scramble. Two people ideally want walking space on both sides.

A double at 135cm suits bedrooms from roughly 2.5m x 3m upwards. A king at 150cm really wants a room of at least 3m x 3.4m to avoid feeling boxed in, especially once you add bedside tables and a wardrobe. In a smaller room, a king can dominate to the point where the space feels tight and hard to move around, which undermines the calm a bedroom should have.

Before you commit, measure the room and mark out the bed’s footprint on the floor with tape or newspaper. Our Will It Fit planner and measuring guide walk you through it, and for the whole layout, see our bedroom layout ideas.

5. When a double is the smarter choice

A double is often the more sensible pick, and not just as a compromise. Choose a double when:

• Your room is average or compact. The double leaves room to move, breathe and add furniture without the space feeling crowded.
• You want the widest choice and best value. Double is the UK’s most popular size, so frames, mattresses and bedding come in the broadest range and often the keenest prices.
• It’s a guest or spare room. A double comfortably sleeps two occasional guests without eating into a room you don’t use daily.
• You sleep solo but like extra space. For one person, a double feels genuinely roomy.

Doubles also pair neatly with storage options if floor space is limited, an ottoman bed in double size lifts to reveal a large storage cavity underneath, reclaiming space you’d otherwise lose. Explore the full double bed range to see frame styles from upholstered to wooden.

6. When a king is worth it

A king size bed earns its keep when space and comfort are your priorities. Go for a king if:

• You share the bed every night. Two adults sleeping together nightly feel the benefit of the extra width most.
• Either of you is tall. The 200cm length keeps feet on the mattress, not dangling over the end.
• You have the room for it. A generous master bedroom can carry a king without losing its sense of space.
• You want a more luxurious, restful feel. The king delivers that hotel-suite spaciousness at home.

A king becomes the centrepiece of the room, so it’s worth choosing a frame you love, whether that’s a statement headboard or a clean, low profile. Browse king size beds and, if you’re weighing up the frame material and style, our how to choose a bed frame guide covers the trade-offs.

7. The true cost comparison

A king costs more than a double across the board, and it’s worth counting every line, not just the frame. The frame itself is usually modestly more expensive in king size. The bigger jump tends to be the mattress, as king mattresses use more material and sit in a higher price bracket. Then there’s the ongoing cost most people forget: bedding.

King duvets, sheets, mattress protectors and fitted covers all cost more than their double equivalents, and because they come in a less common size than doubles, the choice can be narrower and the prices firmer. Over years of replacing worn bedding, that difference adds up. When you’re budgeting, factor in:

• The bed frame.
• The mattress (often the largest single cost).
• At least two sets of bedding in the correct size.
• A mattress protector and, if you like them, a topper.

If your budget is tight, a double frees up money you can put towards a better mattress, which does more for your sleep than the extra 15cm of width. If comfort and space are the priority and the budget allows, the king is a worthwhile investment. You’ll find both sizes across the wider beds range.

8. Mattresses, bedding and storage

Whichever size you choose, the mattress is where your money buys the most comfort. Match the firmness to how you sleep: side sleepers generally want a softer-to-medium feel that cushions the shoulder and hip, while back and front sleepers prefer firmer support that keeps the spine aligned. The same principles apply to both sizes.

Always buy bedding in the exact UK size, a king duvet on a double bed drowns it, while a double duvet on a king leaves cold gaps at the edges. Keep a spare set so you can strip and wash without leaving the bed bare. For storage, both sizes come as ottoman or divan-style frames with drawers or lift-up bases, which is invaluable in smaller homes. If you’re kitting out the whole room, coordinate the bed with matching bedroom furniture and bedside tables for a pulled-together look.

9. Buying with confidence

Once you’ve settled on double or king, ordering from Elystra Living is designed to be reassuring from checkout to bedroom. Your new bed arrives on fast tracked delivery, so you’re not left waiting or guessing, and every order is covered by our 30-day returns policy, giving you time to be sure it’s right for your room. If you’d rather spread the cost, especially useful when you’re buying the frame, mattress and bedding together, Klarna interest-free instalments let you pay in stages at no extra cost. Take your measurements, decide whether space or budget leads your decision, and when you’re ready, browse the full range of double beds and king size beds to find the frame that fits your room and your rest.