Illustration of sweating baby

It is important to make sure that your baby is a comfortable temperature – not too hot or too cold. The chance of SIDS is higher in babies who get too hot.

A room temperature of 16-20°C, with light bedding or a lightweight well-fitting baby sleep bag that is comfortable and safe for sleeping babies.

It can be difficult to judge the temperature in the room, so use a room thermometer in the rooms where your baby sleeps and plays. A simple room thermometer is available to buy from The Lullaby Trust online shop. For more information please call 020 7802 3200.

Advice on room temperature is intended as a guide. Every baby is different, so while it’s important to be informed about overheating you need to check your baby regularly to see if he or she is too hot. Feel the baby’s tummy or the back of their neck (your baby’s hands and feet will usually be cooler, which is normal). If your baby’s skin is hot or sweaty, remove one or more layers of bedclothes.

Babies who are unwell need fewer, not more bedclothes. Babies do not need to wear hats indoors, nor sleep under a duvet or quilt.

Remember that the safest place for your baby to sleep is in the same room with you for the first six months – this will be especially helpful in judging the temperature they will be sleeping at. 

Temperature: FAQs

How can I check if my baby is too hot?

The best way to check on your baby’s temperature is by putting your hand on the skin on their tummy or the back of their neck. Don’t use their hands or feet as a guide as they will always feel cooler than the rest of their body.

If your baby is too hot you will feel the skin is hot, slightly clammy or sweaty, and you will need to remove some layers.

I’m worried about my baby overheating in warm weather, what can I do?

We appreciate how difficult it can be to keep your baby’s room between the ideal 16-20⁰C in the warmer months, knowing that overheating can pose a risk. If the room where the baby sleeps is difficult to cool, follow the ‘summer rules’ of lighter bedding and clothing and open the bedroom door and a window, if it is safe to do so.

You might also like to use a fan to cool the room, but don’t aim it directly on the baby.

It is also important to ensure that your baby has sufficient fluids if bottle-fed, by offering cooled, boiled water to babies under six months or just water from the tap for babies over six months. Fully breastfed babies don’t need any extra water until they start eating solid food.

My home is below the ideal temperature in the winter, should I keep the heating on all night?

It is rarely necessary to keep your heating on all night, and adding an extra layer will usually help. Remember not to add a hat to your baby when they are indoors, as their head is important for
maintaining their body temperature by releasing heat.

If you do feel your home is too cold and you want to leave the heating on all night, make sure it is set at a low temperature, and certainly no higher than 20⁰C.

Why do babies who are unwell need fewer layers?

When babies feel unwell, with a cold or fever, they may be warmer than usual. It is important that you put fewer layers on an unwell baby so they have the opportunity to lower their body temperature – don’t feel tempted to wrap an unwell baby up more than usual.

If your baby shows signs of being significantly unwell you should seek medical advice. You may also find it helpful to use our Baby Check guide to monitor your baby’s symptoms.