What Is the Best Bedroom Temperature for Sleep?

Most people know the feeling of lying awake in a room that is simply too warm. The duvet goes off, then back on, the pillow gets flipped to the cool side, and sleep keeps slipping away. Temperature is one of the quieter influences on a night's rest, and one of the easier ones to change. This answer looks at what tends to help, why, and how to make your own room more comfortable without buying anything new.

Why does temperature matter for sleep at all?

As evening turns to night, the body naturally lets its core temperature drift down a little. That gentle cooling is part of the signal that it is time to rest. A bedroom that is warm and close works against this, which is why hot nights often bring lighter, broken sleep and more waking. A room that is very cold can be unsettling too, because tense, shivery muscles do not relax easily. What most of us are aiming for is a room that feels pleasantly cool when you first get into bed and comfortable once you are under the covers.

So what is the ideal number?

Sleep guidance usually points to the cooler side of ordinary room temperature, somewhere in the mid to high teens in Celsius. See it as a place to begin experimenting, not a target to hit. People differ a great deal: some run hot, some feel the cold, and the right setting also depends on your bedding, nightwear and whether you share the bed. A simple test works better than any figure. If you regularly wake up sweaty or kick the covers off, the room or the bedding is probably too warm. If you wake curled up and chilly, it is probably too cool.

How can I cool a bedroom down without air conditioning?

• Keep daytime heat out. Close curtains or blinds on the sunny side during the hottest part of the day.
• Air the room in the evening. Open windows once the air outside is cooler than inside, and create a through-draught if you can do so safely.
• Swap the bedding. A lighter duvet, cotton or linen sheets and breathable nightwear make more difference than people expect.
• Use a fan sensibly. Moving air feels cooler on the skin. Some people find the hum soothing; others prefer it pointed away from the face.
• Turn off what you do not need. Chargers, lamps and laptops all give off a little warmth in a small room.
• Try a lukewarm shower. Warm rather than cold water before bed can help the body shed heat afterwards.

And if my room is too cold?

Layers are usually kinder than turning the heating right up. A warmer duvet or an extra blanket you can push aside, socks for cold feet and a closed window on frosty nights are all simple fixes. If you use a hot-water bottle or an electric blanket, follow the safety instructions carefully, check them for wear, and never leave an electric blanket switched on through the night unless it is designed for that. Keeping the room only slightly warmer, rather than hot, tends to suit sleep better than a toasty room with the radiator on full.

What about sharing a bed?

Partners often disagree about temperature, and it is a surprisingly common source of tossing and turning. Two single duvets of different weights on one bed is a simple compromise that many couples swear by. The warmer sleeper gets the lighter one; the colder sleeper keeps the cosy one.

Could night sweats be something else?

Sometimes a hot night is not about the room at all. Hormonal changes around menopause commonly bring hot flushes and night sweats, and our piece on menopausal well-being looks at everyday ways people cope with them. Alcohol in the evening, spicy late meals and some medicines can also make you feel warmer at night.

It is worth booking a chat with a GP if you are regularly soaking the bedclothes, if night sweats come with weight loss you cannot explain, a fever or a general sense of being unwell, or if heat at night has started out of nowhere and keeps happening. These are usually not serious, but they deserve a proper look rather than another fan.

What else in the room helps?

Temperature works alongside darkness and quiet. A cool room that is also dim and calm is far more inviting than one that is cool but bright and noisy. The way you spend the last half hour matters too, which is why we also looked at whether reading before bed helps or hinders. Small changes tend to add up: a slightly cooler room, a lighter duvet and a settled wind-down can turn a restless night into an ordinary, unremarkable one, and that is exactly what good sleep should feel like.