Too hot? Too cold? Dressing your baby for sleep changes with the seasons — here’s a simple guide for every temperature, and how to tell when you’ve got it right.
What Should My Baby Sleep In?
The basics: a fitted onesie or footed pajamas as the base layer, plus a swaddle for newborns or a sleep sack once they’re older — and never loose blankets in the crib.
Dressing Baby for Bed With a Swaddle or Sleep Sack
Think of the swaddle or sleep sack as one warm layer. What goes underneath changes with the room temperature — the cooler the room, the more complete the layer beneath.
What Should Baby Wear Under the Swaddle or Wearable Blanket?
Under a mid-weight sack: a long-sleeve onesie in mild weather, footed pajamas in cool weather, and just a short-sleeve onesie when it’s warm — in a real heatwave, a diaper alone under a muslin layer is enough.
How to Dress Baby for Sleep In Summer Months
In summer, less is more: a 0.5 TOG sack or a muslin swaddle over a short-sleeve onesie. Keep the nursery shaded during the day so it stays cooler at night.
Two layer picks parents reach for: the Woolino 4 Season sleep sack for year-round use, and this lightweight summer sleep option.
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Does My Baby Really Need a Sleep Sack?
Need one? No — but it’s the easiest way to keep baby warm safely once they outgrow the swaddle, with no blanket to kick off or pull over the face.
How to Tell if Baby is Cold at Night?
Check the chest or the back of the neck: cool to the touch means add a layer; warm and dry is perfect. Hands and feet normally run cool — don’t judge by them.
Baby Sleepwear Temperature Guide
As a guide: above 75°F — a onesie, with a 0.5 TOG layer if needed. 70–74°F — a onesie or light pajamas plus 1.0 TOG. 65–69°F — long sleeves or pajamas plus 1.0 to 2.5 TOG. 61–64°F — footed pajamas plus 2.5 TOG, and consider warming the room a little.
What is a TOG rating, and should I pay attention to it?
TOG measures how warm a fabric is — and yes, it’s worth paying attention to. It turns “how many layers?” into one simple number you can match to your room temperature.
Helpful Tips for Choosing Baby Bedtime Clothes
Choose breathable natural fabrics, skip hats indoors, and avoid overheating — it’s a bigger risk than a slight chill. Feel baby’s chest at your first night check until the routine feels automatic.
