A booster seat raises your child to the right height so the car's seat belts fit properly. Your child is ready for a booster when they outgrow the height or weight limit for their car seat. Don't be in a rush to move your child to a booster, because they're safer in a car seat with a harness.
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A booster does exactly what its name suggests: It boosts your child high enough for your vehicle's lap and shoulder belts to restrain them safely – with the belts over the stronger places on their body, across the chest and the hips.
After your child outgrows a car seat with a harness, a booster seat is the next step. Your child will be riding in a booster seat for many years, so take time to choose a good one. In fact, you may need more than one. You may want a booster for each of your family's vehicles and for any other vehicles your child regularly rides in.
Advertisement | page continues belowSee the best booster seats according to experts and parents in the BabyCenter Community.
There are two types of boosters:
High back booster. If your vehicle has no head rest and a low seat back, a high back booster will provide support behind your child's head. It may also be more comfortable for a child who falls asleep in the car, because it provides a cradle for their heads.
Backless booster. A backless booster can be used if your vehicle has a seat back that's high enough to support your child's head. Your child's ears should be below the top of the seat back or head rest. Backless boosters are less expensive than high back boosters and easier to transport (from car to car, for example).
All-in-one car seats (3-in-1 and 4-in 1 seats) convert to a booster seat after having served as an infant seat, a rear-facing car seat, and a forward-facing car seat. Some (4-in-1 seats) also convert from a high-back to a backless booster. (A convertible car seat transitions from rear facing to forward facing, but not into a booster.)
Some boosters (often all-in-one seats) are equipped with a LATCH (Lower Anchors and Tethers for Children) system to connect them to the car. These connectors latch on to special metal anchors in the vehicle. (Note that there are weight limits for using lower anchors, so be sure to check your manual.) Boosters without LATCH – the most common – are held in place by a child's weight and the fastened seat belt.
Seat belts are still required to fasten your child in a booster that has been installed with a LATCH system. (When a LATCH system is used to install a harness car seat, it's used in place of the seat belt for installation. And your child is fastened into the harness, not the seat belt.)
Advertisement | page continues belowWithout a booster seat, an adult seat belt can actually cause injury during a car crash rather than prevent it. For example, if the lap belt rests on your child's tummy (which it's likely to do without a booster), they could suffer stomach, liver, or spleen damage in an accident.
And if the shoulder belt rests against their neck rather than their chest, it can cause neck injury. Or your child may try to move it under their arm (where it could crack their ribs and damage internal organs) or behind their back (where it offers no protection against head, neck, and spinal injuries).
Children ages 4 to 8 who use a booster seat reduce their chance of a crash-related injury by 45 percent when compared with seat belts alone. One study found that in states with booster seat laws, the death rate among 7-year-olds was 25 percent lower for children than in states without booster seat laws.
The American Academy of Pediatrics (AAP) and The National Highway Traffic Safety Administration (NHTSA) recommend that all children who have outgrown their harness car seat continue to ride in a booster seat until they're big enough to fit in a seat belt correctly.
Your child is ready to use a regular seat belt only when they can keep their back against the car seat, their knees naturally bend over the edge of the car seat, and their feet stay flat on the floor of the car. The lap belt should rest naturally below their belly, touching the tops of the thighs, and the shoulder belt should be centered between their shoulder and neck.
Advertisement | page continues belowUsing a booster seat for your child until a specific age, weight, or height is probably the law in your state. But the requirements vary widely. To learn about car seat laws where you live, visit the Saferide4Kids Opens a new window website.
No matter what the law says, it's wise to use a booster seat until your child no longer needs one to be properly protected in a vehicle. In 2020, more than 63,000 kids were injured in car crashes, and 607 children died. More than a third of those children weren't properly restrained, which means that a booster seat could have prevented many deaths.
A child can ride in a forward-facing car seat until they outgrow its height and weight limits, which – depending on the seat – can be 65 pounds or more and 49 inches tall. (Check your car seat manual.)
Don't be in a rush to move your child to a booster, because they're safer in a car seat with a harness. Each transition – from rear-facing to forward-facing car seat, from car seat to booster – comes with a decrease in protection.
Advertisement | page continues belowYour child can graduate from the booster seat once they can wear a seat belt correctly without one. This usually happens when a child reaches 4 feet 9 inches in height and is between the ages of 8 and 12.
Most 3-, 4-, 5- and 6-year-olds aren't big enough for a booster seat. The average 5-year-old is about 3 feet 7 inches tall and about 40 to 41 pounds, under the limits for forward-facing car seats. The average 6-year-old is about 44 to 45 pounds and 3 feet 9 inches tall. That means they should stay in their car seat, which is safer, rather than switching to a booster seat too soon.
In fact, many 3-, 4-, and 5-year-olds are still small enough to ride in a rear-facing car seat, which is safest for children. Most convertible seats (which can be changed from rear to forward facing) are safe for children to ride rear-facing up to at least 40 pounds. (Check your car seat manual.)
Look at the maximum weight and height limits of your child's car seat for the rear-facing position, and keep them rear facing until they outgrow the weight or height specified. When they're too big to ride rear facing, you can turn the car seat around to face forward.
Once your child graduates to a forward-facing seat, keep them in it until they reach the maximum height or weight limit specified by the manufacturer. This may be 65 pounds or more.
Advertisement | page continues belowOnce your child weighs more or is taller than the forward-facing limit for their car seat, they should use a booster seat to allow the vehicle lap and shoulder seat belt to fit properly.
The NHTSA provides a car seat finder Opens a new window that will help you determine – according to your child's age, height, and weight – the best car seat for them.
Yes, backless booster seats are safe. They serve to position your child so they can be protected by a seat belt. Backless booster seats may be as safe as high back boosters, though there aren't many studies comparing the two.
One study concluded that seatbelt fit varied greatly among boosters of all kinds, but that backless boosters generally produced better lap belt fit than high back boosters. It also concluded that high back boosters resulted in more consistent shoulder belt fit because they have belt routing guides near the shoulder.
Another small study of injuries to children 4 to 8 years old in side impact crashes found that high back booster seats offered better protection (a 70 percent reduction in injury risk) than backless boosters, which didn't show a statistically significant reduction in injury when compared to seat belts in side impact crashes.
Advertisement | page continues belowSome experts suggest that high back boosters may better protect a child in the case of a crash because they provide better protection for a child's head, neck, and torso. This may be especially true if your rear seat has a low back and if the high back booster has significant side wings. (The padded wings are also useful if your child tends to fall asleep in the car.)
The best type of booster for your child is the one that positions them best for using the seat belt correctly, and that may depend on their size and what kind of seats you have in your car.
Test the booster. Boosters are designed to work with your car's lap and shoulder belts, so they're easy to install. Before deciding to keep the booster seat you've purchased, test it in your vehicle, with your child.
Place the seat on top of your car's seat and make sure it sits flat against the seat (and doesn't tip over easily). Have your child sit in the booster. Fasten the seat belt and check to see if it fits your child correctly. Check that they're all the way against the back of the seat, with their knees bending at the edge of the seat cushion. If they're too small for the booster, their legs will stick straight out and they may slouch or slide forward in the seat, both of which can be dangerous.
Also check the position of the seat belts while your child is sitting in the booster and the belts are fastened. The lap belt should cross their hips – not their belly – and touch the top of their thighs. The shoulder belt should land on their shoulder – not their neck or upper arm – and cross the center of their chest.
Advertisement | page continues belowMake sure your child's ready for a booster. One mistake many parents make is putting their child in a booster seat before they're truly big enough to use it safely. While the instructions on some all-in-one car seats say they can be used without the harness starting at 30 pounds, this is really true only for a very tall, thin child who's grown too tall for the harness but doesn't yet weigh 40 pounds.
Most kids can and should continue using the harness until they exceed the manufacturer's height or weight limit. This is especially true if your child tends to be active in the car, because they may wiggle out of a seat belt or push off the shoulder belt. (This is much more difficult when they're strapped into a five-point harness).
Make sure the booster is in the right spot. The safest place for most booster seats is in the center of the rear seat, so your child is best protected from a side-impact crash. The problem is that many vehicles have only a lap belt in the center back, rather than lap and shoulder belts. (A lap belt should never be used on its own to anchor a booster seat.)
If this is true of your vehicle, position your child's booster on either side of your backseat. It's easier to see your child if they're on the right side of the car, rather than directly behind you. This also makes it easier and safer for them to get out of the car when you're parked on a busy street.
If you have two kids in the car, booster seat placement will depend on the kind of seat belts you have as well as the contours of your backseat. If possible, it's best to put one child in the center and one on the right side of the rear seat (the curb side). But if sitting close together is an invitation for your kids to poke, pinch, and grab each other (distracting you from safe driving while you play referee), you'll probably need a buffer zone in the center.
Advertisement | page continues belowIn that case, put the younger child on the right side so you can check on them more often. If your car is an older model that has only lap belts in the rear seat, you have a real dilemma. Your best bet in that case is to purchase a retrofit kit and have shoulder belts installed.
Don't let any child younger than 13 ride in the front seat (with or without a booster seat), especially if you have an air bag on the passenger side. Air bags may be lifesaving for adults, but they can cause serious head and neck injuries to children when they inflate.
When the booster isn't being used, secure it with a seat belt so that it doesn't get thrown in a collision or sudden stop.
Use the booster's belt-positioning clips. If your child's booster came with belt-positioning clips – either on the sides of a high-back booster or attached to a special strap on a backless model – use them if you need to. These clips ensure that the shoulder belt crosses your child's torso correctly. However, you don't need them if your car's shoulder belt actually lands on your child's shoulder (rather than their neck or upper arm) and crosses the middle of their chest without the guides. Check your instruction manual for directions on using the clips if necessary.
Don't use any products, such as seat belt adjusters, that didn't come with the booster seat, however. If your child has the correct booster for them, the seat belt should cross their body in the correct places without additional products.
Advertisement | page continues belowMake sure your child always uses the booster seat. If your child often rides with grandparents or a neighbor, consider purchasing a separate booster for their car. If they ride in a carpool, ask about booster use.
And in your vehicle, don't make exceptions. If your child views riding without a booster as a positive thing, they're more likely to balk at using it regularly. Explain that the booster makes the seat belts more comfortable for them and enables them to better see out the window. And, of course, stress that as their parent, it's your job to keep them safe.
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