October 23, 2026

What Should Baby Wear to Sleep? A Simple Guide to Safe, Cozy Nights

We're wrapping up Safe Sleep Awareness Month with one of the most common questions new parents ask: what should my baby actually wear to bed?

Since babies shouldn't sleep with loose blankets, what they wear does a lot of the work of keeping them warm. The goal is simple: cozy, but never too hot. Here's how to get it right at every stage.

This guide is for general information. Always follow your pediatrician's advice and the instructions that come with your baby's sleepwear.

Why sleepwear matters

The American Academy of Pediatrics (AAP) says infant sleep clothing, like layers or a wearable blanket (sleep sack), is preferred over blankets and other coverings to keep a baby warm. A safe sleep space should stay free of loose bedding and soft objects.

At the same time, overheating is a known risk factor for SIDS. So the aim is to dress your baby warmly enough that a blanket isn't needed, without over-bundling.

A simple rule of thumb: dress your baby in no more than one layer more than you'd wear to feel comfortable in the same room.

Stage 1: Newborns and the swaddle

Many newborns love being swaddled. According to the AAP, when done correctly, swaddling can help calm infants and promote sleep. To swaddle safely:

Always place baby on their back to sleep, every nap and every night.
Use a thin, breathable blanket. The AAP recommends only a thin blanket for swaddling.
Snug at the chest, loose at the hips. Baby's legs should be able to bend up and out at the hips.
Keep it secure so it can't come loose and cover baby's face.
Stop as soon as baby shows signs of trying to roll over. Some babies start working on rolling as early as 2 months.

Under the swaddle: a single light layer is usually enough, such as a soft cotton gown or onesie.

Shop the stage:

Organic Pre-folded Swaddle — breathable organic muslin, in Muslin, Pearl, Daffodil, Blush and Mint
Organic Nimble Swaddle
Organic Newborn Knotted Gown — an easy, soft first layer for the newborn weeks, in Daffodil, Blush, Mint and Pearl

Stage 2: Ready to roll? Switch to a sleep bag

Once your baby shows signs of rolling, it's time to retire the swaddle and move to a sleeveless sleep bag (also called a wearable blanket or sleep sack). It keeps baby warm while leaving their arms free.

The AAP notes that sleep sacks that don't swaddle and that let baby move freely can be used for as long as you like. A few things to look for:

The right size. A bag that's too big can let baby slip down inside it. The neck and armholes should fit well so baby's head can't slip in.
The right weight for the room. Many sleep bags carry a TOG rating (Thermal Overall Grade). The lower the TOG, the lighter the fabric; the higher the TOG, the warmer. Choose based on your nursery's temperature, not the weather outside.
No weights. The AAP recommends against weighted sleep sacks, swaddles and blankets.

Shop the stage:

Lightweight Sleep Bag — for warmer rooms and layering flexibility, in Blush, Daffodil, Pearl and Mint
Cozy Sleep Bag (1.5 TOG) — a little extra warmth for cooler nights, in Pearl, Daffodil and Blush

How to tell if baby is too warm or too cold

Don't go by hands and feet; they're often cooler than the rest of the body, and that's normal. Instead, feel baby's chest or the back of their neck.

Too warm: sweating, damp hair, flushed cheeks, or a hot chest. Remove a layer.
Too cool: chest or back feels cool to the touch. Add one light layer.

A simple room thermometer in the nursery takes a lot of the guesswork out of choosing what to wear.

What to skip

Hats indoors. The AAP advises against hats during indoor sleep (outside the first hours of life), since they can cause overheating.
Loose blankets, even thin ones, once baby is out of the swaddle.
Weighted sleepwear of any kind.
Outerwear. Take off coats, snowsuits and jackets once you're indoors.
Anything too big, or anything with strings or ties that could wrap around baby or ride up over their face.

Don't forget the sheet

What's under your baby matters too. Use only a snug, fitted sheet on a firm, flat mattress: no extra pads, pillows or bumpers.

Waterproof Cotton Crib Sheet — for those inevitable midnight leaks, in Muslin, Muslin Hearts, Pearl, Mint, Daffodil and Blush

Your quick bedtime checklist

Baby on their back
One light layer plus a swaddle (newborns) or a sleep bag (rollers)
Sleep bag weight matched to the room
No hat, no blanket, no weights
Snug fitted sheet only
Chest check: warm and dry, not sweaty

Cozy and kind: that's what sleep should feel like for your little one. Shop our Safe Sleep Essentials to build a bedtime routine you can feel good about.