The best bedroom temperature for good sleep — how the right bedding helps

There is a reason most people sleep best in a cool room. As evening turns to night the body lowers its own internal temperature, and a room that is a few degrees too warm can make it harder to relax and fall asleep. The question of the best bedroom temperature is therefore not about personal taste alone — it is tied to how the body itself prepares for sleep. In this guide we go through what leading sleep sources highlight about bedroom temperature, why the body cools down at sleep onset, and how your choice of bedding and duvet can help you maintain an even, pleasant temperature throughout the night.

What is the best bedroom temperature?

Many experts point towards a relatively cool bedroom. The American Sleep Foundation describes the ideal room temperature for sleep as around about 18°C, with a broader recommended range of roughly 15.6–20°C for most adults (Sleep Foundation). In everyday Swedish life this often lands at a benchmark around 16–18°C — cool, but not cold. 1177 Healthcare Guide also highlights coolness as a factor: "If the bedroom is dark, quiet and cool it is easier to fall asleep" (1177 Healthcare Guide, Sleep School).

It is worth remembering that exact degree figures are benchmarks rather than rules. How cool feels right varies between individuals, and factors such as age, clothing and your particular bedding play a part. See the numbers as a starting point to fine-tune from — not a definitive answer.

Why cool and not warm?

A room that is too warm forces the body to work to shed heat, which can make it harder to settle. A cool room instead works together with the body's own signals that it is time to sleep. At the same time you want to avoid being cold — the goal is a pleasant coolness where the duvet and bedding handle the fine-tuning closest to the body.

Why the body cools down at sleep onset

According to the Sleep Foundation, the body's internal temperature begins to fall about two hours before you fall asleep, as the body releases the sleep hormone melatonin. The cooling happens partly through increased blood flow to the hands and feet, so heat can be drawn away from the body's core (Sleep Foundation). A cool bedroom simply seems to work in harmony with this natural rhythm.

It also explains a common experience: sticking your feet out from under the duvet when it gets too warm. The body actively seeks to shed excess heat. A sleep climate that allows this process — rather than working against it — can feel more restful. (This is general information about the sleep environment and not medical advice; for persistent sleep problems, consult a healthcare professional.)

The role of bedding: how the right material holds the temperature

The room temperature sets the frame, but it is the bedding and duvet that decide the microclimate closest to the skin. Here the choice of material makes a big difference. A tightly woven yet airy cotton bed linen can release heat and moisture, while the duvet's filling decides how much heat is retained.

Percale — cool and breathable

Percale is a tight, plain-woven cotton quality with a fresh, crisp feel. It breathes coolly and draws away moisture, which makes it a natural choice for anyone who easily gets warm at night or sleeps in a room that tends to run on the warm side. Explore our percale bedding if you are after a lighter, cooling bed. For an extra-soft yet still breathable variant, there is also our Supima bedding in long-staple cotton.

The duvet — how to regulate the warmth

Where the bedding cools, it is the duvet that warms. Here it is about matching the filling and warmth grade to the room and the season:

• Down duvets give a lot of warmth relative to their weight and are airy and light — often appreciated when the bedroom is kept really cool.
• Microfibre duvets are a good option with an even, reliable warmth and are easy to care for.
• Warmth grade rather than room temperature is often the key: in a cool room you can choose a warmer duvet and still sleep well.

See our full range of duvets to find a warmth grade that suits your bed. If you'd like help choosing the right one, read our guide How to choose the right duvet.

Build a bed that follows the seasons

The best bedroom temperature is not static — it shifts with the season. In summer, when the nights are light and warm, many benefit from cool percale bedding and a lighter duvet. In winter, when the room is kept cool but the air is dry, a warmer duvet can make the bed cosy without the room needing to be heated.

Think of the bed as a layered system that you adjust over the year. A complete duvet cover set gives a coherent foundation that you then complement with the right duvet for the season. For a deeper look at how to switch between seasons, read Summer bed vs winter bed.

Small adjustments that make a difference

• Air out the bedroom before bedtime so the room has time to cool.
• Choose bedding in breathable natural materials, rather than dense synthetic blends closest to the skin.
• Adapt the duvet's warmth grade to the room — it's easier than constantly changing the thermostat.
• Let the bedding air and dry properly between washes for a fresh feel.

If you'd like to delve deeper into how textiles and sleep connect, we have gathered more in the article Bedding and sleep.

Frequently asked questions

What is the best bedroom temperature for sleep?

A common benchmark is a cool bedroom around 16–18°C. The Sleep Foundation cites about 18°C as ideal, with a range of roughly 15.6–20°C for most adults. Exactly what feels right varies between individuals, so use the figure as a starting point.

Why do people sleep better in a cool room?

The body lowers its own internal temperature before sleep, partly by drawing away heat via the hands and feet. A cool room works together with this natural process, which according to the Sleep Foundation can make it easier to fall asleep. This is general information, not medical advice.

Which bedding is coolest in summer?

Percale in cotton is a natural choice when you want a cooling bed. The tight but airy weave breathes and draws away moisture, which is often experienced as fresh and cool on warm nights.

Down or microfibre duvet if I want a cool bedroom?

Both work well. Down duvets give a lot of warmth relative to their weight and are light and airy, while microfibre duvets offer an even warmth and are easy to care for. In a cool room you can choose a warmer duvet and still sleep comfortably.

How do I adapt the bed between summer and winter?

Think in layers: cool percale bedding and a lighter duvet in summer, a warmer duvet when it gets colder. Then you can keep the room cool all year round and let the bedding and duvet handle the fine-tuning of the warmth.