Last updated: October 2026
The best temperature for sleep for most adults is a cool bedroom of around 16 to 18°C, with breathable bedding you can add to or kick off. Your core body temperature needs to drop for you to fall asleep. Warm hands and feet help that happen, so sleeping with socks on is fine if they’re comfortable.
Below: the ideal bedroom temperature by age, why a cooler room helps, the truth about socks, heating on or off in a UK winter, sleeping in the heat and a safe temperature for a baby’s room.
What is the best room temperature for sleep?
The Sleep Charity puts the ideal bedroom temperature at around 16 to 18°C. US sleep experts give a similar figure of about 18°C. The NHS doesn’t give a number for sleep, but it does say you may find it easier to sleep in a room that is quiet, dark and cool, and it lists a room that’s too hot or cold as a common cause of insomnia.
Treat it as a starting point. What matters most is the air under your covers: 16°C with a thick duvet can feel just right, and freezing with a thin sheet.
| Who | Suggested bedroom temperature | Where it comes from |
|---|---|---|
| Most adults | About 16 to 18°C | The Sleep Charity |
| Living with a health condition | At least 18°C in winter | NHS winter health advice |
| Babies | 16 to 20°C | The Lullaby Trust |
Older people may sleep better a little warmer. In a US study of older adults sleeping at home, sleep was most efficient with the bedroom at 20 to 25°C, and worse at 25 to 30°C. If 16°C feels too chilly, don’t force it.
Why a cool bedroom helps you sleep
Your core body temperature follows your body clock. It starts to fall in the evening, as melatonin rises, and is lowest in the early hours. Falling asleep and a falling core temperature go together.
To shed that heat, your body opens up the blood vessels in your hands and feet. In a Swiss sleep lab study, how warm people’s hands and feet were compared with their trunk predicted how fast they fell asleep better than core temperature, melatonin or how sleepy they felt.
A cool room makes that heat loss easier. A hot one gets in the way. A review of thermal comfort and sleep found that in real life, with bedding and nightwear, a hot room leads to more waking and less deep sleep and REM sleep. Humid heat is worse still. Cold made less difference to sleep stages, as long as people had enough bedding, though it still affected heart rhythm during sleep.
It’s also why a warm bath 1 to 2 hours before bed is popular: it draws blood to your skin, so you lose heat faster afterwards. Pair it with the rest of a wind-down routine and the other sleep hygiene habits that have good evidence behind them.
Sleeping with socks on: good or bad?
For most people, sleeping with socks on is fine, and it may help if cold feet keep you awake. Warm feet widen the blood vessels in your skin, which helps heat leave your body.
The best known study is small. Six young men slept in a 23°C room with and without bed socks. With socks, they fell asleep on average 7.5 minutes faster, slept 32 minutes longer and woke less often. Their core temperature didn’t change; their feet simply stayed about 1.3°C warmer. Six people is a tiny sample, so treat it as a promising hint, not proof.
- Choose loose, soft, breathable socks. Avoid tight elastic tops that leave deep marks.
- Wear a clean pair rather than the ones you’ve worn all day.
- Take them off if you get hot. Overheated feet that sweat will wake you up, not help.
- Don’t wear compression socks in bed unless a health professional has told you to.
If your hands and feet are always cold, or your toes change colour in the cold, read why am I always cold? and mention it to your GP.
Heating on or off at night in winter?
It depends on who you are. The NHS says to heat your home to a temperature that’s comfortable for you, and at least 18°C in the rooms you regularly use, including the bedroom. It says this is particularly important if you have a health condition. It also advises keeping bedroom windows closed at night in winter.
If you’re fit and healthy, a cooler bedroom with warm bedding is fine and suits most people’s sleep. A sensible middle ground for a UK winter:
- Warm the bedroom before bed, using a timer, then let it drift cooler overnight.
- Heat the rooms you use, rather than the whole house, and close doors to keep the heat in.
- Close thick curtains at dusk to cut draughts.
- Warm the bed, not the room: a hot water bottle or electric blanket, used exactly as the instructions say, plus layers you can remove.
- Watch for condensation. Moisture from showers, cooking and laundry condenses on cold walls and windows, and damp and mould can harm your lungs. Don’t dry clothes in the bedroom, and ventilate for a while during the day.
See also tired in winter.
Too hot to sleep: summer, hot flushes and night sweats
In a heatwave, the NHS suggests closing windows, curtains and blinds during the day and opening them at night once it’s cooler outside. Electric fans can help while the temperature is below 35°C. Swap the duvet for a sheet or a lighter tog and wear thin cotton nightwear, or none.
Sometimes the heat comes from inside. Hot flushes and night sweats are common in perimenopause, and a warm room and heavy bedding can make them worse. Your body also runs slightly warmer in the days before a period, which is one reason for insomnia before your period. If you and your partner differ, try two duvets of different weights. A weighted blanket adds warmth, so keep the room cooler if you use one.
Too hot or too cold? Quick fixes
| Problem | Quick fix |
|---|---|
| Can’t drop off, feet like ice | Loose bed socks, or warm your feet with a bath or shower 1 to 2 hours before bed |
| Waking hot and sweaty | Lighter duvet, breathable cotton sheets, room nearer 16 to 18°C |
| Bedroom too warm in summer | Curtains closed by day, windows open at night, a fan |
| Freezing bedroom in winter | Timer to warm the room before bed, a hot water bottle, extra layers on the bed |
| Partner runs hotter or colder | Two single duvets of different weights |
| Condensation on windows | Ventilate by day, no laundry drying in the bedroom |
| Hot flushes at night | Cool room, layered bedding, see our hot flushes guide and your GP |
Still lying awake once the room is right? Try these ways to fall asleep fast.
Best room temperature for a baby
The Lullaby Trust recommends a room temperature of 16 to 20°C for babies, so they don’t get too hot. Overheating raises the risk of sudden infant death syndrome (SIDS).
- Use a room thermometer.
- Use light bedding or a lightweight baby sleep bag, not a duvet or quilt.
- Babies don’t need hats indoors.
- Check your baby’s temperature by feeling their chest or the back of their neck. Hands and feet are usually cooler, which is normal. If the skin feels hot or sweaty, remove a layer.
- In hot weather, dress them in fewer layers and never point a fan straight at them.
Our products are for adults only. Speak to your health visitor or GP if you’re worried about your baby’s sleep or temperature.
A calm bedtime drink
A warm, caffeine-free drink is a simple cue to wind down. Our Magnesium Glycinate Sleep Complex is a berry-flavoured powder with magnesium bisglycinate and citrate, glycine, L-theanine and chamomile. Magnesium contributes to the normal functioning of the nervous system and to the reduction of tiredness and fatigue. Read more in magnesium for sleep.
A cooler, drier bedroom also helps keep dust mites down; see how to reduce dust mites in the bedroom.
If cold feet keep you awake and your toes change colour, see our guide to Raynaud’s in your feet.
FAQs
What is the best temperature for sleep?
For most adults, a cool bedroom of around 16 to 18°C, with bedding you can adjust. If you have a health condition, the NHS advises keeping the bedroom at least 18°C in winter.
Is 20°C too warm for a bedroom?
Not necessarily. Many younger adults sleep better a little cooler, but older adults often sleep well at 20°C or a bit above. If you wake hot or sweaty, lower the heating or use lighter bedding.
Is it bad to sleep with socks on?
No. Loose, clean, breathable socks are fine and may help you fall asleep faster if your feet are cold. Take them off if you get too hot, and avoid tight or compression socks unless advised.
Should I leave the heating on at night?
If you have a health condition, the NHS advises at least 18°C in the rooms you use, including the bedroom. If you’re healthy, a cooler bedroom with warm bedding is fine.
Is it better to sleep in a cold room?
A cool room is better than a hot one, because heat causes more waking and less deep and REM sleep. Too cold isn’t ideal either, so use enough bedding to feel comfortable.
What temperature should a baby’s room be?
The Lullaby Trust recommends 16 to 20°C. Use light bedding or a baby sleep bag, no hat indoors, and check your baby’s chest or the back of their neck.
Sources
- The Sleep Charity, via EA HealthWell. Sleep environment.
- NHS Every Mind Matters. How to fall asleep faster and sleep better.
- NHS. Insomnia.
- NHS. Winter vaccinations and winter health.
- NHS. Heatwave: how to cope in hot weather.
- The Lullaby Trust. Room temperature.
- UK Health Security Agency and DLUHC. Understanding and addressing the health risks of damp and mould in the home. GOV.UK.
- Sleep Foundation. Best temperature for sleep.
- Okamoto-Mizuno K, Mizuno K (2012). Effects of thermal environment on sleep and circadian rhythm. Journal of Physiological Anthropology.
- Harding EC et al (2019). The temperature dependence of sleep. Frontiers in Neuroscience.
- Kräuchi K et al (2000). Functional link between distal vasodilation and sleep-onset latency? American Journal of Physiology.
- Ko Y, Lee JY (2018). Effects of feet warming using bed socks on sleep quality and thermoregulatory responses in a cool environment. Journal of Physiological Anthropology.
- Baniassadi A et al (2023). Nighttime ambient temperature and sleep in community-dwelling older adults. Science of the Total Environment.
- Haghayegh S et al (2019). Before-bedtime passive body heating by warm shower or bath to improve sleep: a systematic review and meta-analysis. Sleep Medicine Reviews.
This guide is general information, not medical advice. Evopure makes the Magnesium Glycinate Sleep Complex.
