How to Swaddle a Baby (Step by Step)

A good swaddle can transform a startled, flailing newborn into a calm, settled one by mimicking the snugness of the womb and taming the startle reflex that jolts babies awake. But swaddling has two non-negotiable safety rules — back-sleeping and stopping at the first sign of rolling — plus a hip-healthy technique. This step-by-step guide, aligned with AAP guidance, shows how to swaddle safely and when to stop.

How to swaddle, step by step

Lay a thin, breathable blanket in a diamond and fold the top corner down a few inches. Place your baby face-up with their shoulders just below the fold. Gently hold one arm at their side, bring that same side of the blanket across the chest, and tuck it under the opposite side of the body. Fold the bottom corner up over the feet, leaving room for the legs to bend. Finally, bring the remaining side across and tuck it, leaving only the head and neck exposed. The wrap should be firm at the chest and roomy at the hips.

Snug arms, loose hips

The defining rule of a safe swaddle: firm around the arms and chest, loose around the legs. You should be able to slip two to three fingers between the blanket and your baby’s chest — snug enough not to unravel, not so tight it restricts breathing. Critically, the legs must be free to bend up and out at the hips; binding them straight and tight can lead to hip dysplasia. Think "burrito on top, sleeping bag on the bottom."

Always place a swaddled baby on their back

A swaddled baby must always be put down on their back to sleep, every time. Side- or stomach-placement of a swaddled baby is dangerous because the wrapped arms cannot help them reposition or clear their airway. Back-sleeping plus a correct swaddle is safe; any other position is not.

When to stop swaddling

Stop swaddling at the very first signs of rolling — often somewhere between two and four months, though it varies. Once a baby can roll, a swaddle that traps the arms prevents them from pushing up or turning their head if they end up face-down, which is a serious risk. The moment you see rolling attempts, transition out, even if the swaddle was working beautifully.

Transitioning out of the swaddle

Make the change gradually if you can: try one arm out for a few nights, then both, or move to a transitional sleep sack with detachable wings, then a standard wearable blanket with the arms free. Some babies protest the change for a few nights as they adjust to more freedom; staying consistent and keeping the rest of the bedtime routine the same helps them settle into the new setup.

The bottom line

Wrap snug at the arms and chest, loose at the hips so the legs can bend, and always lay your swaddled baby on their back. Watch closely for the first signs of rolling and stop swaddling immediately when they appear, moving to an arms-free sleep sack. Done right, swaddling is a safe, effective soothing tool for the newborn weeks.