Hot days can feel daunting with a small baby — they can't tell you they're too warm, and they overheat faster than we do. The good news is that a handful of simple habits keep them comfortable and safe. Take a breath; you've got this.
Keep the fluids up
Babies lose water quickly in the heat, but how you top them up depends on age.
- Under 6 months: breastmilk or formula is all they need — no water, juice or other drinks. Offer more frequent feeds; breastfed babies often want shorter, more often. Breastmilk naturally adjusts to give them more fluid, so follow their cues.
- Around 6 months and over: keep milk feeds going as usual and you can offer small sips of cooled, boiled water in a cup alongside solids.
Watch for signs of good hydration: 6–8 wet nappies a day and pale, mild-smelling wee. Fewer wet nappies, a dry mouth, a sunken soft spot, dark wee or unusual sleepiness can signal dehydration — contact your GP or child-health nurse.
Dress for the weather
Less is more on a hot day.
- One light, loose layer of natural fabric (cotton) is usually plenty.
- A wide-brimmed hat outdoors to shade the face and neck.
- A good rule of thumb in the heat: dress baby in the same number of layers you're comfortable in, or one fewer — and in real heat, that may simply be a singlet and nappy.
Never leave your baby in a car
This is the one that can't wait.
A baby's body heats up three to five times faster than an adult's, which is why cars are so dangerous. When travelling, use sunshades on the windows, run the air-conditioning, and check that your baby isn't getting too hot in their car seat — the harness and padding trap warmth.
Shade and sun
Babies under 6 months should be kept out of direct sunlight — their skin is thin and burns easily.
- Stay in the shade, especially between 10am and 3pm when UV is strongest.
- Use a pram cover that lets air flow (avoid draping a blanket over the pram, which can trap heat).
- For babies under 6 months, sunscreen isn't recommended as the main protection — rely on shade and clothing, and you may use a little SPF30+ on small areas like the back of the hands. For older babies, apply broad-spectrum SPF30+ or higher and reapply.
Guidance is broadly aligned here: Australia's Cancer Council and Red Nose, the AAP, and WHO all emphasise shade and covering up over sunscreen for the youngest babies.
Safe sleep doesn't change
It's tempting to strip everything away or add a fan right onto baby, but the safe-sleep rules stay exactly the same in the heat.
- Always place baby on their back to sleep (back-to-sleep), for every sleep.
- Keep the cot clear — no loose bedding, pillows, bumpers or soft toys.
- Use lighter bedding or a lower-tog sleeping bag, or just a singlet and nappy if it's very warm.
- Keep the room cooler with fans or air-con, curtains drawn during the day, and good airflow — but don't aim a fan or cooling directly at your baby.
A room temperature of around 16–20°C is often suggested as comfortable, but don't worry about chasing an exact number — focus on dressing baby lightly and checking they're not too hot.
Spotting overheating
Feel your baby's chest or back of the neck (not hands and feet, which are often cooler) — they should feel warm, not hot or sweaty.
| Watch for | What to do |
|---|---|
| Flushed, sweaty or hot to touch | Move to a cool spot, remove a layer |
| Rapid breathing, restless or unusually sleepy | Offer a feed, cool them down |
| Fewer wet nappies, dry mouth, dark wee | Offer extra feeds, monitor closely |
| Fever, very hard to wake, or you're worried | Seek medical advice promptly |
The takeaway
Offer more feeds, dress them lightly, stay in the shade, keep safe-sleep the same, and never leave them in a car. If something feels off, you are always right to check in with your GP or child-health nurse — that's exactly what they're there for.