Most babies sleep in a bassinet from birth until somewhere between 3 and 6 months old. The exact timing depends on your baby’s size and physical development, not a fixed date on the calendar. Once your baby starts rolling over, pushing up on their hands and knees, or reaches the weight limit printed on the bassinet, it’s time to move to a crib.
What Determines When to Stop
Every bassinet has a manufacturer-specified weight and height limit, and that limit is your first hard deadline. Most bassinets max out between 15 and 20 pounds, though some go up to 25. You’ll find the exact number on a label on the product or in the manual. If your baby is a fast grower, you could hit that ceiling well before 3 months.
Physical milestones matter just as much as weight. The moment your baby can roll from back to belly, push up onto hands and knees, or sit up independently, the bassinet is no longer safe, even if they’re technically still under the weight limit. A baby who can sit up unassisted could lean over the shallow side walls and fall out. Bassinets are built with side walls as low as 7.5 inches under load, which is plenty for a newborn lying flat but dangerously shallow for a baby who’s mobile. Whichever milestone comes first, rolling or reaching the weight cap, that’s your signal to transition.
Why Bassinets Work Well for Newborns
The American Academy of Pediatrics recommends that babies sleep on a firm, flat mattress in their own sleep space, and a bassinet meets that standard. Federal safety regulations require that the sleep surface angle not exceed 10 degrees head-to-toe and 7 degrees side-to-side, and that the mattress not sag more than 1.5 inches under the baby’s weight. These specs keep a newborn lying flat and reduce the risk of positional suffocation.
Bassinets also make room sharing easy. The AAP recommends that infants sleep in the same room as a parent (but on a separate surface) to reduce the risk of sleep-related death. A bassinet fits beside your bed in a way that a full-size crib often can’t, giving you quick access for nighttime feedings while keeping the baby on their own firm surface. Bedside bassinets that attach to the edge of your mattress take this a step further, letting you reach the baby without getting up. Sleep medicine specialists generally consider these safe because they maintain a separate sleep surface while keeping the baby close.
One important distinction: bedside bassinets are not the same as in-bed co-sleepers, which sit on top of your mattress. In-bed co-sleepers have been linked to infant deaths and are now illegal under the Consumer Product Safety Commission’s Infant Safe Sleep Rule, which took effect in 2022.
Safe Sleep Basics While Using a Bassinet
Always place your baby on their back. Keep the bassinet completely empty: no blankets, pillows, stuffed animals, or bumper pads. The only things in there should be the baby and a fitted sheet over the firm mattress that came with the product. If you need to replace the mattress, use one specifically designed for your bassinet model. Federal standards now cover aftermarket bassinet mattresses to ensure they meet the same firmness and fit requirements as the original.
Avoid letting your baby sleep in a swing, car seat, or bouncer as a substitute for a bassinet. These devices position the baby at an angle that can restrict their airway, especially in the first few months when they lack the neck strength to reposition themselves.
Making the Move to a Crib
Some babies switch to a crib without fuss. Others resist the change because a crib feels bigger and less enclosed than what they’re used to. If your baby struggles with the transition, start by using the crib for daytime naps only. This lets them get comfortable in the new space during lower-pressure sleep periods before you make the switch at night too.
One technique that helps: put your baby down when they’re drowsy but not fully asleep. This teaches them to fall asleep in the crib itself rather than being transferred after they’ve already nodded off, which can cause them to wake and protest the unfamiliar surroundings. If your baby’s crib is in a separate room, spending some daytime hours in that room before the full transition helps the space feel familiar.
The transition doesn’t need to happen overnight. Some families take a week or two, alternating between bassinet and crib, and that’s fine. The only scenario where you shouldn’t delay is if your baby has already hit a physical milestone like rolling. At that point, the crib needs to become the primary sleep space right away, regardless of how the adjustment is going.