A UK heatwave can turn an ordinary feed, nap or pushchair trip into something parents need to think about more carefully. Babies are especially vulnerable to hot weather, so the goal is simple: reduce heat exposure, support normal feeding and know the warning signs that need medical help. Keeping baby cool in a heatwave does not require complicated gadgets, but it helps to make small changes before the hottest part of the day.
Keep the room as cool as you can
Try to stop the nursery or living room heating up in the first place. Close curtains or blinds during the day, particularly on sunny windows. If it is hotter outside than inside, keep windows closed during the hottest hours, then open them when the outdoor temperature drops and it is safe to do so. Turning off unnecessary lights and electrical equipment can also reduce extra heat indoors.
A room thermometer is useful because guessing can be difficult. The Lullaby Trust recommends a sleep-room temperature of 16°C to 20°C where possible. During a heatwave that may be difficult to achieve, so focus on lighter clothing and bedding and check your baby regularly. A fan can help circulate air, but do not point it directly at your baby.
Reduce layers at sleep time
Dress your baby for the actual room temperature rather than the season. In very hot conditions, a short-sleeved vest or just a nappy may be enough. If you use a baby sleep bag, follow the manufacturer’s tog guidance for the temperature and avoid adding unnecessary bedding.
Keep the usual safer-sleep basics in place: put your baby on their back on a firm, flat sleep surface and keep their head uncovered indoors. To check whether they are too warm, feel their chest or the back of their neck. Hot, sweaty or clammy skin can be one of the baby overheating signs that tells you to remove a layer. Hands and feet can naturally feel cooler, so they are not the best guide.
Keep direct sun off your baby
NHS guidance says babies under six months should be kept out of direct sunlight. Older babies should also spend as much time in the shade as possible, especially between 11am and 3pm when the sun is strongest in the UK summer.
For babies aged six months and over, use sunscreen with at least SPF 30 and protection against both UVA and UVB, alongside lightweight clothing and a wide-brimmed sunhat. Sunscreen is extra protection rather than a reason to stay in strong sun for longer.
Do not cover the pram with a blanket
A common instinct is to drape a muslin or blanket over a pushchair to create shade. The NHS advises against this because covering the pram can contribute to overheating. Use a parasol or suitable sunshade that keeps direct sunlight off while allowing airflow, and check your baby frequently. Never leave a baby in a parked car or another small enclosed space, even briefly.
Adjust feeds carefully in hot weather
Feeding is an important part of baby hot weather safety. Fully breastfed babies under six months do not normally need extra water before they start solid foods. In hot weather, they may want to breastfeed more often, sometimes with shorter feeds. Responsive feeding and watching wet nappies are practical ways to judge how things are going.
If your baby is formula fed and under six months, NHS advice says small sips of cooled boiled water may be offered during hot weather in addition to usual milk feeds. Do not weaken formula by adding extra water; prepare it exactly according to the instructions. Once a baby is around six months and eating solids, offer sips of water from a cup or beaker while breast milk or infant formula remains the main drink during the first year.
Know the signs of dehydration and heat illness
Keeping newborn cool also means noticing changes that suggest heat is affecting them. NHS-listed signs of dehydration in a baby include fewer wet nappies than usual, few or no tears when crying, sunken eyes, a sunken soft spot on the head, drowsiness or irritability. Seek urgent advice from a GP or NHS 111 if you are worried about serious dehydration; for a child under five, call 111 rather than relying on the online service.
Heat exhaustion can cause tiredness, a high temperature, excessive sweating, pale or clammy skin, vomiting, thirst or irritability. Move the child to a cooler place, remove unnecessary clothing and start cooling them. If they are not improving within around 30 minutes, seek urgent medical help. Heatstroke is an emergency. A very high temperature, hot skin without sweating, fast breathing, confusion, a seizure or loss of consciousness are warning signs, and 999 should be called.
A practical routine for a very hot day
Imagine the forecast says the temperature will peak in the afternoon and stay warm overnight. In the morning, ventilate the house while the air outside is cooler. Before direct sun reaches the nursery, close the curtains. Keep your baby in light clothing, continue normal feeds and avoid unnecessary outings around midday. If you go out, stay in shade and use a pram parasol rather than a blanket.
Later, when the outdoor temperature falls, safely open windows to let cooler air through. A cool bath before bed can help your baby feel comfortable. Check the room thermometer, reduce nightwear to suit the temperature and feel your baby’s chest or neck before settling them. This routine is usually more effective than trying to cool an already overheated room at bedtime.
Frequently asked questions
Can a baby sleep in just a nappy during a heatwave?
Yes. In very hot weather, NHS and safer-sleep guidance allow for minimal sleepwear, including just a nappy when appropriate for the room temperature. Keep following normal safer-sleep guidance and check that your baby is not hot or clammy.
Should I give my breastfed newborn water when it is hot?
Fully breastfed babies under six months generally do not need extra water. They may breastfeed more frequently during hot weather. If you are concerned about feeding, hydration or wet nappies, ask your midwife, health visitor, GP or NHS 111 for advice.
Is a fan safe in a baby’s room?
A fan can help circulate air, but do not aim it directly at your baby. Keep cords safely out of reach and continue checking the room temperature rather than assuming the fan has made the room cool enough.
What is the safest way to shade a pushchair?
Use a parasol or suitable sunshade that blocks direct sunlight without enclosing the pushchair. Avoid placing a blanket or muslin over the pram, and check your baby regularly for warmth, sweating or discomfort.
Keep heatwave safety simple
The safest approach is a collection of small, steady choices: shade the room early, reduce clothing and bedding, protect your baby from direct sun, maintain age-appropriate feeding and watch for changes in behaviour or wet nappies. Those habits make keeping baby cool in a heatwave more manageable and help you spot quickly when ordinary heat discomfort may be becoming a health concern.
