What Should My Baby Wear to Sleep?
If you’ve ever stood over the cot at 2am asking, “Is this too many layers? Not enough? — hi, hello, I made this for you. Temperature matters because babies can’t regulate heat like we do. Too hot can raise the risk of sleep-related incidents; too cold can mean restless, fragmented sleep. The sweet spot is keeping baby comfortably warm without overheating — and that starts with the room, the right TOG, and the right layers.
Why temperature matters for sleep (quick + simple)
Overheating = risky & unsettled. The AAP advises watching for signs like a hot chest, sweating, or flushed skin; avoid hats indoors and aim for just one more layer than you in the same environment.
Aim for a cool room. In the UK, the Lullaby Trust recommends 16–20°C (it can feel cool to adults — that’s normal). A room thermometer (part of most baby monitors) helps you check it at a glance.
TOG 101 (so you can stop guessing)
TOG = “thermal overall grade” — the higher the number, the warmer the sleeping bag/sleep suit. Think of TOG like the toggle on warmth. Typical baby options: 0.2, 0.5, 1.0, 1.5, 2.5, 3.5. Brands give temp ranges for each; always check your product’s chart, but here’s a useful rule of thumb pulled from major UK/ANZ brands:
0.2–0.5 TOG: warm rooms / heat waves
1.0 TOG: mild rooms
1.5 TOG: cool-mild rooms
2.5 TOG: cooler rooms (UK most of the year)
3.5 TOG: very cold rooms / winter without central heating
What should my baby wear? (By room temperature, in °C)
Use this as a starting point and adjust to your baby. Check their chest/neck (not hands/feet) — add/remove a layer if too cool or sweaty. Keep sleep space clear; no hats.
*Layers assume a sleepsack/sleeping bag with armholes. If using a swaddle (newborns only), ensure it’s TOG-rated, breathable, and stop swaddling at first signs of rolling.
Always place baby on their back on a firm, flat surface with no loose bedding.
Important: The ideal room temp is 16–20°C, so focus on dressing for that range when you can. If your room runs hotter/colder, use the chart to adapt and work on the room environment (ventilation, heating, cooling) first.
How to tell if your baby is too hot or too cold
Too hot: sweaty hair, damp chest/back, flushed skin, fast breathing. Remove a layer and choose a lower TOG.
Too cold: cool chest/neck (hands/feet can be cool and still normal), mottled skin, unsettled sleep. Add a thin layer or move up a TOG.
FAQs (the ones you DM me at 11pm)
Do I need blankets if I use a sleeping bag?
No. A fitted, TOG-rated sleeping bag replaces loose blankets, which is safer and keeps warmth consistent.
Which brand’s chart should I trust?
Use the chart for the exact bag you own (they test differently). If you’re switching brands, re-check their guide; ranges can differ a little.
Is 2.5 TOG really “UK standard”?
It’s the most-used for ~16–20°C rooms — common for UK bedrooms — with a bodysuit or sleepsuit underneath.
Can my newborn wear a hat to sleep?
No. Hats increase overheating risk; keep the head uncovered indoors.
What about swaddling?
Great for newborns. Use a breathable, TOG-rated swaddle; keep hips loose.
Quick setup checklist (print/save this)
Room 16–20°C (use a thermometer).
Pick a TOG for the room temp (check your brand’s chart)
Dress in light layers; baby usually needs one more layer than you.
Back to sleep, clear cot (no loose bedding, pillows, toys), no hats indoors.
Check baby’s chest/neck to fine-tune layers.
The calm, confident way to dress for sleep
You don’t need guesswork or 47 tabs open. Start with the room temp, match the TOG, add sensible layers, and then let your baby be the guide. A comfortably dressed baby sleeps more soundly — and so do you.