What temperature should your baby's room be once the heating goes on?

Quick answer: Keep your baby's room between 16 and 20°C, which the NHS says is comfortable and safe for sleeping babies. At that temperature a sleepsuit and a 2.5 tog sleeping bag usually works. To check how warm your baby is, feel their chest or the back of their neck, not their hands.

What parents need to know

Once the heating comes on, a nursery can climb past 20°C without you noticing, especially if the cot is near a radiator. A room thermometer by the cot gives you a reading instead of a guess, and the NHS recommends using one.

When the house turns cold, it's natural to want to add layers. The NHS is clear that babies are better off cooler than too hot, because overheating raises the risk of sudden infant death syndrome (SIDS). This applies to every sleep, day or night, up to 12 months.

Which sleeping bag tog for which room temperature

Sleeping bags have a tog rating, which tells you how warm they are. The NHS lists these ranges for commercial sleeping bags. Use them as a starting point and check the manufacturer's label too.

A sleeping bag needs to fit well around the shoulders so your baby's head can't slip down inside. Don't put any other bedding on top of it.

What your baby wears underneath

In winter, the NHS says a sleepsuit plus a sleeping bag, or a sheet and/or blanket, should be fine. Change the clothing under the bag to suit the tog and the room temperature.

If the room is cooler than usual

If your baby is in a sleeping bag and seems cold, the NHS advises adding one more layer of clothing, not extra blankets. A thermometer reading below 16°C means the room needs warming.

If the room runs warm

Use a lower-tog bag and fewer layers. On the warmest nights, a vest or just a nappy is enough.

If you use blankets instead of a sleeping bag

Choose lightweight cellular cotton blankets, which keep your baby warm and still let air through. Avoid thick, fleecy or padded ones.

Lay your baby on their back in the feet-to-foot position, with their feet at the foot of the cot. Tuck the blanket in firmly no higher than the shoulders. Don't double it over: a folded blanket counts as two.

What stays out of the cot, even in winter

Soft items around a baby, especially near the head, can cause overheating and raise the risk of SIDS. The NHS advises keeping the cot clear of anything that could cover your baby's face or head.

Take off hats and extra clothing as soon as you come indoors, even if it wakes your baby.

• No hats indoors or in the cot
• No duvets, pillows, cot bumpers or loose blankets
• No sleeping pods, nests or anything else used to keep your baby in place
• No hot water bottle or electric blanket
• No cot positioned next to a radiator, heater or fire, or in direct sunlight

How to check if your baby is too hot

Small babies aren't good at controlling their own temperature. They can overheat from too much clothing, too much bedding or a room that's too warm.

1. Feel the chest or neck. Put your hand on your baby's chest or the back of their neck. Cool hands and feet are normal and don't tell you much
2. Look for sweating. Damp hair, a sweaty neck or a hot tummy means they're too warm
3. Remove a layer. Take off one or more layers of clothing or bedding, then check again a little later
4. Check the thermometer. If the room is above 20°C, turn the heating down or move to a lower-tog bag

Frequently asked questions

Does a baby with a fever need extra layers in winter?

Usually not. The NHS says that, even in winter, most babies who are unwell or feverish don't need extra clothes. Contact 111 or your GP if you're worried. NHS guidance

What about naps in a warm car?

Take off hats and extra layers as soon as you get into a warm car, bus or train. It's fine for your baby to fall asleep in the car seat while you're travelling, but take them out once you arrive. NHS guidance

Can the mattress affect how warm my baby gets?

Yes. A mattress that isn't firm enough makes it harder for a baby to lose heat. Your baby's head shouldn't sink in by more than a few millimetres. NHS guidance

My baby was premature. Does any of this change?

Follow the same safer sleep advice, but for a year from your baby's due date rather than their birth date. NHS guidance