Newborns sleep in a firm, flat sleep surface like a crib, bassinet, or portable play yard, dressed in a lightweight sleep sack or swaddle with nothing else in the sleep space. That’s the short answer. The longer answer involves choosing the right piece of equipment for your home, picking appropriate sleepwear for the room temperature, and knowing which popular products to avoid entirely.
Cribs, Bassinets, and Play Yards
The three main options for a newborn’s sleep space are a full-size crib, a bassinet, and a portable play yard (sometimes called a pack-and-play). All three are considered safe as long as they meet current federal safety standards. Full-size cribs last the longest since most convert to toddler beds, but they take up more room. Bassinets are smaller, lighter, and easier to keep next to your bed in those early weeks. Portable play yards split the difference and work well for travel or smaller living spaces.
Whichever you choose, the mattress matters most. It should be firm and fit tightly against the sides with no gaps where a baby’s face could become wedged. The U.S. Consumer Product Safety Commission requires that crib slats be no more than 2 3/8 inches apart, roughly the width of a soda can, so a baby’s body can’t slip through. Check for missing or loose screws, cracked slats, and corner posts that stick up more than a fraction of an inch, since clothing can catch on them. For mesh-sided bassinets or play yards, the mesh openings should be smaller than the tiny buttons on baby clothing, with no tears or loose threads.
A used crib can be fine if it meets current standards, but older models (especially drop-side cribs, which were banned in 2011) should not be used.
What Goes Inside the Sleep Space
Nothing. The mattress gets a single fitted sheet, and that’s it. No blankets, no pillows, no bumper pads, no stuffed animals, no pillow-like toys, no quilts, no comforters, no mattress toppers. These items increase the risk of suffocation, entrapment, and strangulation. A baby who rolls into any of them can have their airflow blocked.
This rule applies every time your baby sleeps, including naps, and stays in place through the first year. The bare-crib look can feel wrong at first, especially if your nursery inspiration came from social media, but a fitted sheet on a firm mattress is exactly what your baby needs.
Swaddles and Sleep Sacks
Since blankets are off limits, your newborn’s warmth comes entirely from what they’re wearing. The two main options are swaddles and sleep sacks.
A swaddle wraps your newborn snugly with their arms against their body, which can reduce the startle reflex and help them settle. Many parents find swaddling essential in the first few weeks. The critical safety rule: you must stop swaddling the moment your baby shows any signs of rolling over. Once a baby can roll onto their stomach, they need free arms to push themselves up and keep their airway clear. Most babies start showing signs of rolling between 3 and 4 months, though some roll as early as 2 months.
Sleep sacks (also called wearable blankets) are the next step. They’re essentially a sleeveless bag your baby wears over their pajamas, leaving their arms free. Sleep sacks can be used from birth and remain safe well into toddlerhood, making them the most versatile option.
Choosing the Right Warmth
Sleep sacks and swaddles are rated by TOG, a measure of thermal resistance. A higher TOG means a warmer product. Here’s a general guide based on room temperature:
- 0.2 TOG: best for warm rooms, 75°F to 81°F
- 1.0 TOG: standard for most homes, 68°F to 75°F
- 2.5 TOG: good for cooler rooms, 61°F to 68°F
- 3.5 TOG: designed for rooms below 61°F
A comfortable room temperature for a sleeping baby is roughly 61°F to 68°F (16°C to 20°C), paired with light bedding or a lightweight sleep sack. In warmer months or if you can’t cool the room down, dress your baby in fewer layers and open a window if it’s safe to do so. The goal is to keep your baby warm without overheating.
Why Overheating Is a Real Risk
Newborns regulate their body temperature poorly, and getting too hot is a recognized risk factor for sleep-related deaths. When a baby overheats, they can have difficulty waking up and getting enough oxygen. Too many clothing layers, blankets, and especially hats worn indoors during sleep can trap body heat. Babies born prematurely are particularly vulnerable because their temperature regulation is even less developed.
A quick way to check: feel the back of your baby’s neck or their chest. If the skin is hot or sweaty, remove a layer. Hands and feet often feel cool on newborns, so they’re not a reliable gauge.
Products to Avoid
Several popular baby sleep products are either unsafe or no longer recommended.
Weighted sleep sacks, swaddles, and blankets have drawn strong warnings from multiple federal agencies. The CPSC, CDC, NIH, and the American Academy of Pediatrics all agree these products are not safe for infants. A newborn’s rib cage is not rigid, and even modest pressure can make it harder to breathe and harder for the heart to beat properly. There is also evidence that weighted products can lower oxygen levels, which may harm a developing baby’s brain. The AAP has compared the situation to inclined sleepers like the Rock ‘N Play, which remained on the market for years before being linked to over 100 infant deaths.
Inclined sleepers and rockers are not safe for unsupervised sleep. Any product that holds a baby at an angle greater than 10 degrees from flat poses a suffocation risk because a baby’s head can slump forward and cut off their airway.
Dock-a-tots, baby nests, and lounger pillows are not designed for sleep, even though they’re often marketed alongside sleep products. The soft, padded sides create the same suffocation risk as placing a pillow in the crib.
Room Sharing Without Bed Sharing
For at least the first six months, and ideally the first year, keeping your baby’s sleep surface in your bedroom significantly reduces the risk of sleep-related death. This means the crib or bassinet sits next to your bed, close enough that you can hear and reach your baby easily for nighttime feeds.
This is different from bed sharing, where the baby sleeps on the adult mattress. Adult beds have pillows, blankets, soft mattresses, and gaps between the mattress and headboard, all of which are hazards. There’s also the risk of a sleeping adult rolling onto the baby. Room sharing gives you proximity and convenience without those risks. A bedside bassinet that sits level with your mattress can make middle-of-the-night feeds much easier while keeping the baby on their own safe surface.
A Simple Setup for Night One
If you’re preparing for a newborn’s arrival, the checklist is reassuringly short. You need a crib, bassinet, or play yard with a firm, flat mattress and a fitted sheet. You need a few swaddles for the early weeks and a couple of sleep sacks (likely in 1.0 TOG for a typical home) for when you transition out of swaddling. A onesie or footed pajama goes underneath, adjusted for the season. That’s the entire sleep setup. No extras, no accessories, no special gadgets needed.