As a sleep consultant who has supported families for over 14 years, I know how many questions can come up around safe baby sleep. A few questions I get asked are: “How do I know if my baby is warm enough at night?” or “What TOG sleeping bag should I use?”
These are completely normal concerns. When you’re caring for a baby, especially a newborn, it can feel as though there’s a lot to remember. The reassuring news is that safer sleep advice does not need to feel complicated. There are clear, trusted guidelines that can help you create a calm, comfortable and safer sleep environment for your baby.
Every baby is different, with some naturally feeling warmer or cooler and your home environment will also make a difference. However, by understanding the basics of safe sleep, room temperature, and how to dress your baby for sleep, you can feel much more confident at bedtime and nap time.
Safer sleep positions and spaces
The safest sleep position for babies is on their back for every sleep, including daytime naps and overnight sleep. NHS safer sleep advice states that babies should be placed on their back to sleep, on a firm, flat mattress, with their sleep space kept clear.
This means avoiding pillows, duvets, loose blankets, cot bumpers, soft toys, pods, nests and bulky bedding. These items can increase the risk of a baby’s face or head becoming covered, or make it harder for them to regulate their temperature safely. The Lullaby Trust also advises that babies are safest in a clear cot or Moses basket, without pillows, duvets, cot bumpers, soft toys or loose bedding.
A well-fitting baby sleeping bag can be a helpful alternative to loose blankets because it helps prevent your baby wriggling down underneath bedding. The key is choosing the correct size and TOG for your baby, as well as a comfortable room temperature.
How to dress your baby for sleep
Keep room temperature in mind as a winter night in a well-heated room may mean your baby will need fewer layers than a cool spring evening in an older house.
A helpful rule is to dress your baby in light, breathable layers that can be adjusted. Rather than adding loose blankets, which can move around the cot, adjust what your baby wears underneath their sleeping bag.
To check your baby’s temperature, feel their chest or the back of their neck. Their hands and feet often feel cooler than the rest of their body, so they are not always the best guide. Your baby should feel comfortably warm, not hot, clammy or sweaty.
Signs your baby may be too warm include:
- Sweating
- Damp hair
- A hot chest or back
- Flushed skin
- Rapid breathing
- Restlessness
Signs your baby may be too cold include:
- A cool chest or back
- Waking frequently due to discomfort
- Skin that feels unusually cool under clothing
If you are unsure, it is usually better to use lighter layers and monitor your baby than to overwrap them. Overheating is something safer sleep guidance specifically advises parents to avoid.
Baby sleeping bag TOG guide
A baby sleeping bag TOG guide can make bedtime feel much easier. TOG simply means how warm the sleeping bag is. The higher the TOG rating, the warmer the sleeping bag.
It is important to choose a sleeping bag that is suitable for your baby’s age, weight and size. The neck and armholes should fit well so your baby cannot slip down inside the bag. The Lullaby Trust notes that baby sleeping bags can be a good safer sleep option, provided they fit well around the shoulders and no extra bedding is added.
Here is a simple guide to common baby sleeping bag TOG ratings:
| Room temperature | Suggested TOG | What baby might wear underneath |
| 24–27°C | 0.5 TOG | Nappy only, or short-sleeved vest |
| 20–24°C | 1.0 TOG | Short-sleeved vest, or lightweight sleepsuit |
| 16–20°C | 2.5 TOG | Long-sleeved vest or sleepsuit |
| Below 16°C | 3.5 TOG, only if suitable | Sleepsuit and vest, depending on baby and manufacturer guidance |
NHS guidance describes 2.5 TOG as suitable for standard room temperatures of 16–20°C, 1.0 TOG for warmer rooms of 20–24°C, and 0.5 TOG for hot weather and warm rooms of 24–27°C.
A 3.5 TOG sleeping bag may be used by some families in very cold rooms, but it is not always necessary and should only be used if it is suitable for your baby and recommended by the sleeping bag manufacturer. Always check the label and product guidance, as different brands may vary slightly.
Most importantly, do not add loose blankets over a sleeping bag. If your baby seems cold, it is safer to adjust their clothing layers or consider whether the room itself needs gentle warming.
Lullaby Trust TOG chart and safer sleep guidance
The Lullaby Trust is one of the most trusted UK sources for safer sleep advice. Many parents find The Lullaby Trust TOG chart and temperature guidance helpful when deciding how to dress their baby overnight.
Rather than relying on guesswork, their advice encourages parents to consider room temperature, use a room thermometer where possible, and dress babies in appropriate layers. The Lullaby Trust recommends a baby room temperature of 16–20°C where possible, as this helps reduce the risk of babies becoming too hot. Their guidance also explains that a baby sleeping bag can be a useful option because it reduces the chance of a baby wriggling under covers and getting their head covered.
As a sleep consultant, I often remind parents that charts are a guide, not a test you have to pass. They are there to support your judgement. Your baby, your room, the fabric of the sleep suit, and the fit of the sleeping bag all play a part.
Baby room temperature tips
The recommended baby room temperature of 16-20°C may feel cooler than some adults expect, but babies do not need very warm rooms to sleep safely.
Here are some practical ways to manage baby room temperature:
- Use a room thermometer: This can help you make more confident decisions, especially during seasonal changes.
- Keep the cot away from heat sources: Avoid placing your baby’s cot next to radiators, heaters, fires or direct sunlight. NHS Wales safer sleep guidance also advises that babies should not sleep next to a radiator, heater, fire or in direct sunshine.
- Adjust layers, not loose bedding: If the room feels cooler, add a vest or sleep suit underneath the sleeping bag rather than placing a blanket over the top.
- Avoid hats indoors for sleep: Babies lose excess heat through their heads, so hats should not be used for indoor sleep unless you have been specifically advised otherwise by a healthcare professional.
- Check the temperature of your baby: A thermometer is useful, but your baby’s chest or back of neck will give you a better idea of whether they feel comfortable.
Common mistakes to avoid
Please remember, these are not here to make you feel worried or guilty. Most parents are simply trying to keep their baby cosy. A few small adjustments can make sleep safer.
- Overdressing: It’s natural to worry about your baby being cold, but overheating can be a concern. Try to avoid too many thick layers, especially if your baby is already in a warm sleeping bag.
- Using hats indoors while sleeping: Hats are not recommended for routine indoor sleep. Once you are inside, remove outdoor hats and extra layers so your baby does not become too warm.
- Adding loose blankets over a sleeping bag: A sleeping bag is designed to replace loose bedding. If you add blankets on top, your baby may become too warm, and the blanket may move during sleep.
- Using weighted blankets or weighted sleep products: Weighted sleep products are not recommended for babies. Choose a lightweight, well-fitting sleeping bag instead.
- Letting your baby sleep unsupervised in car seats, swings or bouncers: It is very common for babies to fall asleep while travelling or being rocked. However, a car seat, swing or bouncer is not intended to be a regular sleep space. Government safer sleep guidance for early years providers states that if a baby falls asleep in a car seat while travelling, they should be moved to a separate sleep space as soon as possible after returning.
Final reassurance from a sleep consultant
After many years of working with families, I know that baby sleep can feel overwhelming, especially when advice seems to come from every direction. However, safe sleep doesn’t have to be perfect to be protective. Small, consistent choices make a real difference.
If you ever feel uncertain about safer sleep advice, your baby’s temperature, or what is right for your individual circumstances, speak to your midwife, health visitor, GP, paediatrician, or refer to trusted safer sleep resources such as The Lullaby Trust and the NHS.
You are not expected to know everything straight away. With gentle guidance and evidence-informed choices, you can create a sleep environment that feels calm, comfortable and safer for your baby. If you would like further support, take a look at how we can help you at BabyWinkz: https://babywinkz.com/services/ and please feel free to reach out to judyclark@babywinkz.com for any questions.
FAQs
1. What is the safest position for my baby to sleep in?
The safest position is on their back for every sleep, both naps and overnight. Once your baby can roll independently, speak to your health visitor if you have concerns, but you should still place them down on their back at the start of sleep.
2. What TOG sleeping bag should my baby wear?
This depends on the room temperature. As a general guide, 0.5 TOG is for warm rooms, 1.0 TOG for mild or warmer rooms, and 2.5 TOG for cooler rooms around 16–20°C. Always check the sleeping bag manufacturer’s guidance.
3. How do I know if my baby is too hot at night?
Feel your baby’s chest or the back of their neck. If they feel hot, sweaty or clammy, remove a layer or reassess the room temperature. Do not rely only on hands and feet, as these often feel cooler.
4. Can I put a blanket over a baby sleeping bag?
It is best not to add loose blankets over a sleeping bag. A sleeping bag is designed to be used instead of loose bedding. If your baby seems cold, adjust their clothing underneath or check whether the room is too cool.
5. What is the ideal baby room temperature?
The commonly recommended baby room temperature is 16–20°C. A room thermometer can help, but it is also important to check your baby’s body temperature by feeling their chest or back of neck.