How to Dress Baby for Sleep. A Mom’s Guide to Dressing Your Baby for Sleep. Tips for Summer, Winter and In Between.
My baby was born in the middle of an excruciatingly hot summer. As our apartment didn’t have any air con (or very good heating, once winter hit), I was stressed.
In the lead-up to my daughter’s birth, I remember Googling furiously. I also messaged all my parent-friends regularly. Ready to order sleep onesies and sleep suits, I had so many questions about dressing baby for sleep.
Although it seems like simple query, finding the right advice about how to dress a newborn for sleep wasn’t quite as easy as it seemed it should be.
Which is why I wanted to share all the experience I’ve gained on the topic since then in one place.
Let Go of the Old Ways
I gave birth in a very traditional European country with a strong cultural aversion to being cold.
While grandmothers the world over share advice to bundle up babies with layers of cozy warmth (wrong!), and to let little ones under 12 months to sleep with blankets (wrong), I was in a place where old ladies literally stopped me and yelled at me on the street, saying my baby was too cold!
In fact, layers and layers of clothing is not advised for babies sleeping. And using blankets before a baby is 12 months is a huge no no. Both practices increase the risk of SIDS.
If you can’t listen to grumpy grandmas, you might be wondering how do you get your infant in the best clothes for sleeping? Every parent wants to ensure their baby is safe and comfortable to sleep. But HOW?
Below, I’ll share my best advice on how to dress baby for sleep.
Note, this is based on my personal experience, with some research into peer reviewed and medical expert sources. However, you should always consult a doctor. And don’t take any of this as medical advice or expertise (because I am definitely not an expert – just a mom who has walked this road before you!).
Finally, these are general guidelines. You’ll need to make changes based on your own home and climate. And take into consideration any medical or developmental concerns your baby might have.
With that caveat out of the way, let’s get on with the sharing…
My Top Tips on How to Dress Your Baby for Sleep
My general rule of thumb when dressing your baby for sleep… have them dress in similar clothes to you, plus one layer.
I think this guideline is logical, because newborns won’t have a blanket or duvet like you will. That one additional layer is the blanket equivalent, with pajamas / sleep suits / onesies underneath.
(Note: A diaper or underwear is not considered as a layer).
If you’re wearing long-sleeved fuzzy pajamas to get through the depths of winter, your baby might need warm PJs plus a wearable blanket.
If you’re sleeping in the buff to stay cool in summer, a sleeveless cotton onesie or zip-up sleep suit may be all your baby needs.
Since we had a summer baby in a hot climate without air con, we often dressed our baby only in a diaper under her swaddle sack for those first few months.
Is There an Ideal Baby Sleep Temperature?
Babies sleep better when they’re comfortable. And that includes a room that’s not too hot, and not too cold.
But when it comes to actual recommended nursery room temperature? It actually lies on the cool side of where you’re probably naturally inclined to set the thermostat.
The most common recommendation for an optimum sleeping environment? Set baby’s room temp to between 68° to 72° Fahrenheit (20° to 22.2°C).
My advice is don’t stress too much about it, or obsess over the thermostat in your home.
But also don’t let the room get too warm.
A room temperature thermometer can help you monitor whether it’s too cool or warm. Even better, many bath thermometers do double duty and measure room temperature, too. This is great for reducing the amount of baby stuff you need.
If you live in an area where summers are scorching, consider installing heat-blocking blackout shades (if you’re on vacation in a hot climate and using a travel crib, there are pack and play blackout tents you can get, but you need to make sure they don’t increase the temperature for your baby and follow all safety guidelines). We use black out shades in our toddler daughter’s room, and keep the shades closed during hot days. Without fail, her room is cooler than the rest of the house.
You can also get a fan to circulate the air and keep the room cool. A fan has the added bonus of adding white noise to help baby sleep. Evidence also suggests circulating air reduces the risk of SIDS.
As the seasons change, be prepared for temperature fluctuations. You know your house and climate best, and should adjust the clothing layers your child wears accordingly.
If it’s cold, consider adding a thicker TOG wearable blanket. On scorching summer nights, peel back the layers – your baby may just wear a short-sleeved sleepsuit or onesie.
Despite what the older generations did, it’s better to have your baby slightly underdressed than over-dressed for sleeping. Overheating carries a greater risk of SIDS.
Banish the Blankets
Remember, blankets under 12 months are a huge no-no! They are a contributing factor to SIDS and are not recommended according to AAP guidance.
A boring crib is a safer crib, so keep it clear of everything. Just a tightly fitting fitted crib sheet and a firm mattress that fits the crib well.
Instead of blankets, you can use zip-up swaddle sacks for warmer weather. I loved these things, and they are safer for hip dysplasia than traditional swaddling techniques.
You can also use a cozy higher tog wearable blanket for cooler nights.
What is a Sleep Sack? Swaddle Sack?
Sleep sacks are a kind of sleeping bag/wearable blanket hybrid. They have arm holes but no foot holes. It’s like your baby is wearing a sleeping bag that allows their arms to stick out.
A swaddle suit is similar, but keeps baby’s arms tightly controlled. Some keep baby’s arms down by their side. Others position their arms up over their head (which lots of babies seem to like when sleeping).
We used both.
We used a zip up swaddle suit instead of a traditional muslin cloth when our daughter was an infant. This helped her feel secure and cozy in her side sleeper bassinet. Once little ones are able to roll over, however, these aren’t safe anymore, because they limit arm movement so much. At that point, we switched to a sleeping bag.
TOG Rating
For both sleeping bags and zip up swaddles, there are many styles available, each with a different TOG rating.
TOG stands for thermal overall grade, and the higher the number, the warmer the fabric. Grades of 1.5 and below are for warm months (spring and summer). Bags with TOG rating of 2 to 2.5 are for cooler weather (winter and fall).
During very warm nights when our daughter was first born, we dressed her in a diaper and a 0.5 tog zip up. During her first winter, we’d dress her in a long sleeve onesie and a 2.5 tog wearable blanket.
Typically, we had 2 bags in different tog ratings for each season, from when our daughter was a newborn until she was 18 months or so. In summer we used a 0.5 tog and a 1 tog, and in winter we had a 1.5 or 2 tog and a 2.5 tog.
Once they are more mobile and can stand in the crib or get into some gymnastics or climbing (particularly during sleep regressions), you might need to ditch the sack!
Should you Swaddle your Sleeping Baby?
A swaddle is a great way to wrap your newborn for sleep and to keep them feeling cozy and protected, like in the womb, and can help if your baby feel secure if they won’t sleep unless held. As well as a cozy fit, swaddling also keeps limbs secure, which often leads to babies sleeping for longer during their nap.
While they can be great for smaller babies, you should stop using them once your baby can roll themselves over, usually at around 4 months.
We chose to use a zip up swaddle bag, instead of doing it ourself with a cloth. We didn’t want to fuss with wrapping her up when we were exhausted in the middle of the night, and we also worried about wrapping her too tightly, which increases the risk of hip dysplasia.
What Should a Baby Wear Under a Swaddle?
Whether you use the traditional method or a zip-up, the question becomes, what should baby wear under a swaddle?
This again depends on the season, temperature, and thickness of the blanket or sack you’re using.
Go back to the golden rule: babies should wear what you wear to sleep, plus an additional layer.
Think of the swaddle as the additional layer. In winter, long-sleeve pajamas under a swaddle might be needed to stay warm, whereas in summer months, dressing your baby in a short onesie, with a thinner muslin swaddle could do the trick.
If it’s a real heatwave, with temperatures upwards of 80 degrees, you can always swaddle your little one just with their diaper to keep them from being fussy and their body from overheating.
Snug Fit for Snug Sleep
When choosing clothing for a baby to wear to sleep, you don’t want anything that is too big for them.
Loose clothing has the risk that it may slip up and over the baby’s head and face during sleep, creating a breathing risk.
It’s also a fire risk, and kids pajamas are made to fit snugly for exactly this reason, or have added fire retardant chemicals.
When choosing a sleeping bag, make sure it has a fitted neck and armholes, and ensure your baby can’t wriggle down into it while snoozing. Don’t use anything that has a hood attached.
Fashion or Function?
Baby clothes are ever so cute, but bear in mind that during night times, the only people likely to see your baby sleeping are you and your partner!
Save the cute outfits for daytime and events. For baby sleep clothing, pick clothes that are comfy, but also easy to remove and dress baby in. After all, you’ll probably have to do some middle of the night feeds and diaper changes, or even change PJs and sheets if your baby pees through their diaper at night.
A Hat to Keep Your Baby Warm?
In the maternity ward, your baby may have looked oh-so-cute wrapped up in a blanket with a matching baby sleep hat. But once you get home it’s time to ditch the hat for naps and sleep time.
Your baby regulates temperature by releasing heat through their head. A hat prevents this, and carries a risk of overheating. Plus, there is a risk a hat falls off or covers your baby’s face while they sleep, adding a risk of breathing difficulties.
Reduce the risk completely, and leave the hat off!
How to Dress Your Baby for Sleep in Different Weather
There’s a common parenting saying that goes something like, “once you get used to something, it changes.”
In my experience, this thought is true for almost every part of parenting, including figuring out what to dress your baby during the night or naps.
Once you do figure it out, they’ll change, or the season will change, and you’ll have a whole new equation to figure out.
How to Dress Baby for Sleep in Winter
In the cold winter chill, you want to ensure your baby keeps warm while in their crib at night.
Generally speaking, you want to layer up while still erring on the side of baby being too cool, rather than too toasty.
This may involve a fleecy sleepsuit, or a cotton, long sleeved PJs. You can then add a warm sleep sack or a warmer swaddle suit on top.
When our daughter was a baby, we found a long-sleeved cotton onesie with a wearable sleeping bag was enough to keep her warm, but everyone’s situation is a bit different.
Some parents are tempted to put blankets down under the mattress to make it warmer and more comfy, especially for little one’s sleeping in a pack and play vs a crib or on a floor bed. This is a no no for safety reasons!
Of course, recommendations on what to wear will change based on your own home, and whether or not you have central heating or drafty windows, as an example.
When dressing your baby in layers, it’s a good idea to check on them regularly to make sure they don’t look or feel warm or sweaty.
If there are any signs you’re baby’s overheating, remove some clothing ASAP. This is especially true when they’re an infant, but you always want to keep an eye on them to ensure they’re not overheating in bed.
How to Dress Baby for Sleep in Summer
When the temperature rises a few degrees you can cool off with the clothing too. Cotton is a breathable fabric that is lightweight and comfortable.
Stick to short-sleeve onesies over the diaper, and a thinner sleeping bag or lightweight swaddle sack for newborns. You can also get a summer baby sleep sack, often made of cotton. They’re breathable and more lightweight for summer months. Or ditch your cotton sleep sacks altogether if it’s super warm, or ditch the sleep onesie under the lightweight sack (i.e. 0.5 tog).
Final Tips
Check on Your Babies – Too Hot or Not?
It’s difficult to know if your baby is truly comfortable considering they aren’t able to communicate with us. As a parent, you are often left trying to decide if their fussing and crying is a sign of hunger, tiredness, or gassiness. Or is it a baby sleeping in an uncomfortable temperature?
If your little one has had their feed, and is wearing a dry diaper but still acting distressed, they may too hot or cold.
As well as fussiness, you can look out for physical signs of overheating too.
Check for a sweaty head, or perspiration around their neck. They may have wet hair from sweating. Their cheeks may be flushed red too, and some children may display a heat rash. Also, check for quickened breathing.
Also remember that a baby’s hands and feet may remain cold to the touch, even if they themselves are too hot, as their circulatory system is still developing.
When in doubt, feel the skin on your child’s tummy, neck, and chest. If these areas are overly warm and sweaty, take fast action to cool your child down. Lowering the room temperature and removing a layer of clothing can help.
On the other end of the spectrum, you also need to ensure that your little one is not too cold. If you notice that your baby’s hands and feet are looking slightly blue in color, it might be time to turn up the heat a couple of degrees or add a layer of clothing.
Can Toddlers Overheat Too?
Once you’re out of the baby stage, know that your toddler can still overheat at night, so consider their layers when getting them into bed.
Your toddler may use blankets, rather than sleep sacks, which means they can usually kick off at night.
But it’s worth checking on your toddler whenever you change their sleepwear. Look for a sweaty head, wet hair, and flushed appearance, and if you spot any – remove a layer!
What Should a Newborn Wear to Sleep? (Quick Summary)
- No hat
- One more layer than what you’re wearing
- Nothing loose in the crib (no blankets)
- No loose clothing or sleepwear
- Err on the side of being cooler
Final Thoughts on How to Dress a Baby for Sleep
Follow the golden rule, of ‘What’s right for me – plus one layer!’ for a cozy sleep for your baby, erring on the side of cooler, rather than overheating. Use a swaddle or sleep sack for the extra layer, and always ditch the blanket completely.
Once you know these basic rules, it’s easier to choose the right sleepwear to dress your baby in for sleeping.
Often thick fleecy onesies and pajamas are too warm, so layers are useful to combat the cold. Check on your baby, too, by feeling their chest and neck to see if they are comfortable or too hot, as they sleep.
Feel free to share this article and tips on what should baby wear to sleep with other parents, who might have similar dressing their baby for sleep worries.
