Safe Sleep Guidelines: The AAP ABCs

Safe sleep comes down to three letters, the ABCs: your baby sleeps Alone, on their Back, in a bare Crib or bassinet. Everything else in the American Academy of Pediatrics safe-sleep guidance builds on those three ideas. They are simple, they are consistent, and following them every single sleep — naps included — is the most protective thing you can do for a baby under one year.

If the details below ever feel overwhelming, come back to the ABCs. They are the whole message; the rest is explanation.

A is for Alone

Your baby sleeps on their own separate surface, with nothing else in it. That means no pillows, no blankets, no bumper pads, no sleep positioners, no stuffed animals, and no other people. A bare sleep space is not a plain choice — it is the safe one. Soft and loose items are a suffocation risk for a baby who cannot yet reliably move their head or push objects away.

"Alone" also means not sharing an adult bed, sofa, or armchair. Sleeping with a baby on a couch or armchair is especially dangerous. If you are feeding at night and feel you might doze off, feed in your bed rather than a chair — and if you do fall asleep, move the baby back to their own flat, firm surface as soon as you wake.

B is for Back

Place your baby on their back for every sleep, day and night, from the very first day. Back sleeping is strongly linked to lower risk, and it does not increase choking — a healthy baby's airway is designed to clear itself in that position. Side and stomach sleeping are not safe for sleep.

Once a baby can roll both ways on their own, you still start them on their back, but you do not need to reposition them if they roll during sleep. That milestone is also the cue to stop swaddling, which we cover in when to stop swaddling.

C is for Crib (bare, firm, and flat)

Your baby sleeps in a crib, bassinet, or play yard that meets current safety standards, on a firm, flat mattress made for that product, covered only by a fitted sheet.

• Firm.The mattress should not indent or conform to the baby's head. If it forms a pocket around the head, it is too soft.
• Flat. The sleep surface must be flat and level, not inclined. Inclined sleepers and products that let a baby sleep at an angle are not safe for sleep.
• Standards-compliant. Use a crib, bassinet, or play yard that meets current CPSC standards, with a snug mattress and no missing hardware. Drop-side cribs are banned and must never be used.
• Bare.Only a fitted sheet — nothing else.

For choosing the sleep space itself, see our best bassinets, best cribs, and best pack 'n plays, and our nursery setup checklist for the whole room.

Room-share, but do not bed-share

The AAP recommends the baby sleeps in the parents' room — on their own separate surface — ideally for at least the first six months. Room-sharing keeps the baby close for feeding and comfort and is linked to lower risk, while bed-sharing (the baby in the adult bed) raises it. A bassinet or play yard beside your bed is the classic room-sharing setup.

Keep loose bedding out — use a sleep sack for warmth

Loose blankets are exactly the kind of soft item safe sleep asks you to keep out of the crib. To keep a baby warm, dress them in a wearable blanket — a swaddle for the early weeks, then a sleep sack once they show signs of rolling. Our roundups of the best swaddles and best sleep sacks cover both.

Avoid overheating

A baby who is too warm is at higher risk, so aim for a comfortable room temperature and dress the baby in no more than one layer more than an adult would wear to be comfortable. Signs of overheating include sweating or a hot chest. A sleep sack in the right weight is usually all a baby needs — skip the hat indoors.

Offer a pacifier at sleep time

Offering a pacifier at naps and bedtime is associated with lower risk. If you are breastfeeding, it is generally suggested to wait until feeding is well established. If the pacifier falls out after the baby is asleep, you do not need to put it back, and if the baby does not want it, that is fine too — never force it or attach it to anything with a cord or clip during sleep.

Tummy time — but only while awake and watched

Tummy time is for building neck and shoulder strength, and it belongs to awake time only, always supervised. It is the opposite of sleep: babies sleep on the back and play on the tummy. A few short sessions a day, working up as the baby grows, is plenty.

Check for recalls

Before using any crib, bassinet, or play yard — especially a hand-me-down — check it against the CPSC recall list (linked in our sources) and confirm it has all its parts and instructions. Register new sleep products so the maker can reach you if a recall is issued.

That is the whole of safe sleep: Alone, on the Back, in a bare Crib, on a firm flat surface, room-sharing without bed-sharing, no loose bedding, not too warm, a pacifier if it settles them, and tummy time only while awake. When it feels like a lot, remember the three letters — they carry the rest.