Quick answer: A newborn does not need a hat indoors or for sleep once you are home. Health Canada says, "Babies do not need a hat when indoors, as it can make them too hot." A hat is useful outdoors: a warm one that covers the ears in cold weather, and a brimmed sun hat plus shade in warm weather.
Few baby questions get such mixed advice. The hospital sends you home with a tiny knit hat, a relative insists the baby will "lose all their heat through the head," and then the safe sleep pamphlet tells you to take the hat off. All of these can be true in the right setting. The answer depends on where your baby is, how warm or cold it is, and whether your baby is awake or asleep.
Below, we walk through each situation using guidance from Health Canada, the Canadian Paediatric Society (CPS), the American Academy of Pediatrics (AAP) and the U.S. National Institutes of Health (NIH).
This article is general information, not medical advice. If your baby was born early, has a health condition, or seems unwell, follow the advice of your doctor, nurse practitioner, midwife or public health nurse.
Hat or No Hat? A Quick Guide by Situation
Use this table as a starting point. The sections below explain each row.
| Situation | Hat? | Why |
|---|---|---|
| Awake indoors at home | No | Health Canada: babies do not need a hat indoors because it can make them too hot. |
| Sleeping (naps and nighttime) | No | CPS: take off hats and items with ties before sleep. NIH: keep baby's head and face uncovered during sleep. |
| In hospital right after birth | Follow your care team | Hospitals manage newborn temperature with drying, skin-to-skin contact, warmers and clothing. |
| Outdoors in cold weather | Yes, one that covers the ears | CPS: babies need extra care and bundling in winter, and ears should stay covered. |
| Outdoors in sun, under 6 months | Shade first, plus a brimmed hat | AAP: keep babies younger than 6 months out of direct sunlight. |
| Coming into a heated store, home or vehicle | Take it off | NIH: hats indoors can make baby too hot, so take the hat off when inside. |
Should a Newborn Wear a Hat Indoors?
No. Once you are home from the hospital, a hat indoors usually adds warmth your baby doesn't need. Health Canada's Safe Sleep for Your Baby guide is direct about it: "Babies do not need a hat when indoors, as it can make them too hot."
The AAP says the same thing in its parent's guide to safe sleep: "Don't put a hat on your baby while indoors once you're home from the hospital." The NIH Safe to Sleep campaign adds that "Wearing hats while indoors can make baby too hot, so take off baby's hat when inside."
So how warm should your home be? Health Canada keeps it simple: "Keep the room at a comfortable temperature," and "If it is comfortable for you, it will be comfortable for your baby too." For clothing, the AAP's rule of thumb is that "Your baby only needs one more layer than you would wear in the same environment to be comfortable." If you're comfortable in a T-shirt at home, your baby likely needs a one-piece and a light sleeper or similar, not a hat on top.
Should a Newborn Wear a Hat to Sleep?
No. Take the hat off before every sleep, including naps. This is one of the clearest points in Canadian and U.S. guidance.
The Canadian Paediatric Society's Caring for Kids page on safe sleep for babies says: "Take off bibs, necklaces, items with ties or hoods, and hats before putting your baby to sleep to prevent strangulation." It also reminds parents that "Overheating increases your baby's risk of SIDS."
The NIH's Safe to Sleep guidance says to "Avoid letting baby get too hot, and keep baby's head and face uncovered during sleep." It explains that babies can overheat "if they are wearing too many layers of clothes and bedding for the room temperature (sometimes called overbundling)."
What should a newborn wear to sleep instead?
Health Canada recommends "simple, fitted sleepwear – like a sleeper," and says it "should keep your baby comfortable at room temperature, so they do not get too hot." If you're worried about cold nights, the AAP suggests you "dress them in layers of clothing or use a wearable blanket" rather than adding loose items to the crib.
The sleep space matters too. Health Canada advises: "Always place your baby on their back to sleep, for every sleep," on "A firm, flat mattress with a tightly fitted sheet," with "No loose, soft items." For a full look at sleepwear layers on cold nights, see our guide on how to dress a newborn for sleep in winter.
What about naps away from home?
The same rule applies. CPS asks parents to make sure everyone who cares for the baby uses the same sleep practices "for naptime, nighttime, at home, in childcare settings and when travelling." At a grandparent's house, a hotel or a friend's place, take the hat off and remove outdoor layers before your baby goes down to sleep.
Why Do Hospitals Put Hats on Newborns?
Hospitals use hats as one part of keeping newborns warm right after birth. It is a clinical routine, not a rule for home.
Children's Hospital of Philadelphia (CHOP) explains in Warmth and Temperature Regulation that "Babies are not as adaptable as adults to temperature change" and "Babies can lose heat rapidly, as much as four times more quickly than adults." Right after birth, "A baby's wet skin loses heat quickly by evaporation and can lose 2° to 3°F," so care teams dry and warm the baby with "warm blankets and skin-to-skin contact with the mother, or another source of warmth such as a heat lamp or over-bed warmer."
Once a baby is stable in an open crib or bassinet, CHOP notes that "Babies are usually dressed in a gown or T-shirt, a diaper, and a hat. A baby can lose large amounts of heat through his/her head." That's the reason for the familiar striped hospital hat.
Does that mean my baby needs a hat at home?
No. The same CHOP page ends with the AAP recommendation "that parents and caregivers avoid overbundling, overdressing, or covering an infant's face or head to prevent him or her from getting overheated." And the AAP's own wording draws the line at the hospital door: no hat indoors "once you're home from the hospital." In hospital, follow your nurses' lead. Packing for the birth? See our newborn hospital outfit ideas.
Does a Newborn Need a Hat Outside in Cold Weather?
Yes. When it's cold outside, a warm hat that covers the ears belongs in your baby's outdoor outfit. CPS notes in its winter advice for parents that "Babies need extra care and bundling because they cannot generate body heat or tell you if they are cold the way an older child can."
For children in general, CPS lists "Wear a hat" and "Always keep ears covered to prevent frostbite" among its winter clothing tips. The AAP's cold weather guidance agrees: "Always remember warm boots, gloves or mittens, and a hat." It adds that "The rule of thumb for older babies and young children is to dress them in one more layer of clothing than an adult would wear in the same conditions," and that "Several thin layers will keep them dry and warm."
In practice, that means a lined hat with ear flaps for cold walks, such as the Deux par Deux baby winter knit hat with ear flaps, listed in sizes 3/6m to 2/3T. Fit tips and more styles are below.
How cold is too cold for outdoor time?
Canadian winters can turn quickly, so it helps to know the thresholds the experts use. For children, CPS suggests you "Consider keeping them indoors whenever the temperature or the wind chill is reported to be -27°C (-16°F) or lower. At these temperatures, exposed skin will begin to freeze." The AAP's winter tips say that "In general, playing outside in temperatures or wind chills below -15° Fahrenheit should be avoided."
Those numbers are written for children playing outdoors. A newborn can't move around to warm up or tell you they're cold, so keep very cold outings short, and ask your health-care provider if you're unsure.
How should a newborn's winter hat fit?
Look for coverage first, then fit:
- Ears fully covered. This follows CPS's advice to always keep ears covered. Ear flaps or a deep crown that sits below the earlobes both work.
- Snug, not tight. The hat should stay in place when your baby turns their head, but it shouldn't leave deep marks on the forehead.
- Eyes and face clear. The brim or cuff should sit above the eyebrows, so it can't slide down over the eyes or nose.
- Matched to the weather. A thin knit may be enough on a cool fall walk. A lined winter hat makes more sense in January.
What about scarves, strings and ties?
For young children, CPS advises: "Use a neck warmer instead of a scarf, and mitten clips instead of a string to prevent choking." It also suggests removing drawstrings from clothing that "could catch on climbing or play equipment." Many baby winter hats have chin ties to keep the flaps over the ears. Use them only while your baby is awake and with you, and take the hat off before any sleep, as CPS advises.
What are the signs of frostbite?
The AAP notes that "Fingers, toes, ears, and noses are most likely to get frostbite," and that affected skin "may become pale, gray and blistered." If you suspect frostbite, the AAP says to "bring your child indoors to gently warm up." The AAP adds, "Don't rub the affected area," and says to call your doctor if numbness continues for more than a few minutes. With a baby, call your health-care provider for any frostbite concern.
Which winter hat should you choose for a baby?
For cold-weather outings, browse winter accessories for baby knit hats (toques) and other cold-weather accessories. Deux par Deux lists its Baby Winter Knit Hat With Ear Flaps and Ears in Off-White with ear flaps, chin ties and a polar fleece lining, in sizes from 3/6m. The brand's Baby Winter Sherpa Hat With Ear Flaps is a trapper-style hat with a polar fleece lining, also starting at 3/6m. Add gloves and mittens to finish the outdoor outfit. For a deeper comparison of styles and fabrics, read our winter hat buying guide for babies. These hats are for outdoor, awake time, not for sleep.
Do Babies Really Lose Most of Their Heat Through Their Heads?
No, that's a myth. But a baby's head is large compared with the rest of the body, so covering it outdoors in the cold still makes sense.
In a 2008 review of common medical myths, pediatricians Dr. Vreeman and Dr. Carroll of Riley Hospital for Children looked at this belief. As summarized by Indiana University School of Medicine, they believe it "likely originated with an old military study where scientists put subjects in arctic survival suits without hats." The subjects "did lose the most heat through their heads, but only because it was the only bare part of their body." With much more of the body exposed, the subjects "would not have lost more than 10 percent of their body heat through their heads." Their takeaway: "Any uncovered part of the body loses heat and will drop the core body temperature proportionally."
Babies are built differently from adults, though. CHOP notes that "A baby's body surface is about three times greater than an adult's, compared to the weight of his/her body," and that "A baby can lose large amounts of heat through his/her head." CPS still tells children to "Wear a hat because a lot of body heat is lost through the head" in winter.
Either way, the practical answer is the same: outdoors in the cold, cover the head and ears along with the rest of the body. Indoors, leave the head uncovered so your baby doesn't get too hot.
Does a Baby Under 6 Months Need a Sun Hat?
Yes, a brimmed hat helps, but shade comes first. In its sunburn and sunscreen advice, the AAP says to "Keep babies younger than 6 months out of direct sunlight." Health Canada's sun tips for parents go further: "Keep babies under one year out of direct sunlight," "Never let them play or sleep in the sun," and "Keep babies in the shade, under a tree, an umbrella, or a canopy."
A hat is your second step. The AAP suggests cool clothing that covers the body and a hat "with an all-around 3-inch brim to shield the face, ears, and back of the neck." CPS's sun advice says to "Cover your baby in loose clothing and make sure they are wearing a hat" and to "Use a stroller sunshade to cover your baby."
What about sunscreen? Health Canada says, "Do not put sunscreen on a baby less than 6 months old without asking your health care provider first." CPS adds that babies this age "can rub it in their eyes and mouth." That's why shade and clothing do most of the work for young babies.
A sun hat also adds warmth, so watch for signs your baby is getting too hot (see below). For older babies, the kids hats and caps collection includes brimmed styles. Our guide to sun clothing for kids covers the rest of the summer outfit.
When Should You Take Your Baby's Hat Off?
Take the hat off as soon as you come indoors, whether that's your home, a store, a restaurant or a heated vehicle. In a Canadian winter, heated spaces feel very warm after a cold walk, and a winter hat and snowsuit hold that heat in.
In its advice for babies who doze off in a stroller, Health Canada's safe sleep guide says to "Take off your baby's snowsuit, raincoat, jacket and other outerwear once indoors" to reduce the risk of suffocation or overheating. The NIH puts it plainly: "take off baby's hat when inside."
A few everyday moments when the hat should come off:
- Walking into a store or mall. Take the hat off and open or remove the outer layer, even for a short errand.
- Getting home after a walk. Remove the hat and outerwear before your baby settles in, and well before any nap.
- When your baby falls asleep. Take the hat off before sleep, wherever your baby is.
For help planning outerwear that's easy to take on and off, see what to wear under a snowsuit and our guide to dressing an infant for winter.
How Can You Tell If Your Baby Is Too Warm?
Check your baby's chest. The AAP advises parents to "Check your baby for signs of overheating such as sweating, a hot chest or flushed skin." The NIH lists "sweating, flushing/red or hot skin, or baby's chest feeling hot to the touch."
If your baby shows signs of overheating, take off the hat and a layer, move to a cooler spot, and check again in a few minutes.
Aim for comfortable, not bundled. For warmth checks during sleep, read how to know if your baby is too hot in a swaddle.
When to get help: If your baby seems unwell or you're worried, contact your health-care provider right away, or call 911 in an emergency.
What About Premature or Low-Birth-Weight Babies?
Follow your care team's instructions. Babies born early or small may need a different plan for keeping warm, especially in the first weeks.
CHOP explains that "Premature and low-birthweight babies usually have little body fat and may be too immature to regulate their own temperature, even in a warm environment." Cedars-Sinai says the same, and adds that keeping babies at a temperature that is not too hot or too cold "is even more important if your baby is sick or premature."
If your baby spent time in the NICU, ask before discharge how to dress them at home and whether they need a hat for any reason. Their advice comes before any general guide, including this one.
What Are the Most Common Newborn Hat Mistakes?
Most mistakes come from treating the hat as an all-day item instead of an outdoor layer. Watch for these:
- Keeping the hospital hat on at home. The AAP is clear: no hat indoors once you're home from the hospital.
- Leaving a hat on for naps. CPS advises taking hats off before every sleep.
- Forgetting the hat in heated places. Stores, homes and vehicles warm up fast. Take the hat off when you go inside.
- Choosing a hat that leaves the ears out. In winter, pick a hat with ear flaps or a deep crown, since CPS advises keeping ears covered.
- Relying on a sun hat alone. For babies under 6 months, the AAP and Health Canada put shade first.
- Adding a scarf. CPS suggests a neck warmer instead of a scarf for young children.
- Buying only the smallest size. Babies grow quickly, so check fit every few weeks.
How Many Hats Does a Newborn Need?
Not many. Hats are for outdoor use, so plan around the weather you'll face in the next few months:
- Born in fall or winter: a warm hat that covers the ears for outdoor time, and a spare for when one is in the wash or gets wet.
- Born in spring: a lightweight hat for cool mornings, and a brimmed sun hat for later in the season.
- Born in summer: a brimmed sun hat, along with shade, a stroller sunshade and light clothing that covers the skin.
For a broader look at newborn wardrobe planning, see where to find newborn hats and clothing. To decide which layers your baby needs outside in general, read should a baby wear clothes outside. Wondering about hair, too? Our guide on cutting a baby's hair before age 1 covers scalp care in sun and cold.
Frequently Asked Questions
Should a newborn wear a hat in the house?
No. Health Canada says babies do not need a hat indoors because it can make them too hot, and the AAP says not to put a hat on your baby indoors once you're home from the hospital.
Should a newborn wear a hat to sleep?
No. The Canadian Paediatric Society advises taking off hats and items with ties before sleep. Dress your baby in a fitted sleeper suited to the room temperature, and keep the head and face uncovered.
Why did the hospital put a hat on my baby?
Newborns lose heat quickly, and CHOP notes that a baby can lose large amounts of heat through the head. Hospitals use hats as one part of temperature care after birth. It's not a rule for home.
Does a newborn need a hat outside in winter?
Yes. Choose a warm hat that covers the ears, as CPS advises keeping ears covered to prevent frostbite. Take it off as soon as you go indoors.
Does a baby under 6 months need a sun hat?
A brimmed hat helps, but shade comes first. The AAP says to keep babies younger than 6 months out of direct sunlight, and Health Canada advises asking your health-care provider before using sunscreen at this age.
How do I know if my baby is too hot in a hat?
Feel your baby's chest. The AAP lists sweating, a hot chest and flushed skin as signs of overheating. If you notice them, remove the hat and a layer.
Is it true babies lose most of their heat through their heads?
No. Researchers traced that idea to a study where the head was the only uncovered body part. Any uncovered skin loses heat, but a baby's head is large for their body, so cover it outdoors in the cold.
The Bottom Line
A newborn's hat is an outdoor layer, not an all-day or sleep item. Indoors and for sleep, leave it off and dress your baby in fitted sleepwear for the room temperature. Outdoors in the cold, choose a warm hat that covers the ears, and take it off when you come inside. In the sun, keep young babies in the shade and add a brimmed hat. When in doubt, check the chest for warmth and ask your health-care provider.
Sources
- Public Health Agency of Canada / Health Canada: Safe Sleep for Your Baby
- Health Canada: Sun safety tips for parents
- Canadian Paediatric Society, Caring for Kids: Safe sleep for babies
- Canadian Paediatric Society, Caring for Kids: Winter safety: Advice for parents and kids (last updated February 2023)
- Canadian Paediatric Society, Caring for Kids: Sun safety (last updated August 2021)
- American Academy of Pediatrics, HealthyChildren.org: A Parent's Guide to Safe Sleep
- American Academy of Pediatrics, HealthyChildren.org: Cold Weather Safety
- American Academy of Pediatrics, HealthyChildren.org: Playing Outside in Winter
- American Academy of Pediatrics, HealthyChildren.org: Sun Safety: Information for Parents About Sunburn & Sunscreen
- NIH, Safe to Sleep campaign: Ways to Reduce Baby's Risk
- Children's Hospital of Philadelphia: Warmth and Temperature Regulation
- Cedars-Sinai: Keeping Your Baby Warm
- Indiana University School of Medicine: Medical Myths for the Holiday Season: True, False or Unproven? (December 18, 2008)
