Medically Reviewed by Mahammad Juber, MD on June 06, 2022
Written by Rebekah KuschmiderCar seats are one of the most effective safety tools for children. Child safety seats reduce the risk of death in an accident by 70%. Even school-age children benefit from staying in child safety seats. Once kids have grown out of their harness seats, they should use a booster seat to ensure that their seat belt fits well and protects them in a crash.
A booster seat is a safety precaution for kids who are too big for a front-facing car seat but too small for a seat belt alone. It is not based on age but on the child's size and weight. Boosters raise kids up so that their upper body is aligned with the shoulder belt of a standard seat belt. Some boosters have headrests that help protect a child's head and neck in an accident.
Children go through several different types of car seats as they grow. Before they meet booster seat requirements, kids must be in an approved car seat with a harness. The harness keeps the child secure in the safety seat to prevent injury in case of a car accident.
Infants and some toddlers need to ride in rear-facing seats that offer extra protection from impacts. These seats meet rigorous safety standards. They offer the best protection to babies and young toddlers.
Children who have outgrown the height and weight limit for a rear-facing seat can switch to a front-facing seat with a harness. Many children can comfortably ride in a front-facing harness seat until they are in elementary school.
Car seats are anchored to the back seat of the car using the seat belts or the LATCH system. All cars manufactured after 2002 have LATCH anchors built into the back seat. With this, you can clip the seat to them so that it won't move out of place.
Booster seats are intended to be positioning devices, and they don't have the impact protections of a harness car seat. The base of a booster may have tethers to attach it to the seat, but many do not. There is no built-in harness on a booster. Instead, the child uses the seat belt to ride securely in the back seat.
You can move your child to a booster once they've gone over the height and weight limit for a front-facing car seat. You can find the specifications for your car seat on the manufacturer's website. Some models have that information printed on the seat itself. Weight limits for a front-facing car seat can go as high as 80 pounds or more. The extended weight limits may be helpful for children with disabilities who may need a car seat longer than other children their age.
Children using a booster need to be able to sit still in a car and keep the seat belt in place. If a child can't properly wear a seat belt, they should stay in a harness car seat, even if they meet the height and weight for booster seats.
Boosters should always be in the back seat of a car. Back seats are the safest place for children in the event of an accident. Aside from the danger of a car accident itself, the impact of airbags can cause injuries to kids.
Convertible car seats. There are some models of harness seats that convert to a booster. Parents can remove the harness but leave the seat anchored to the back seat of the car. There will be belt positioners on the shoulders.
High-backed boosters. High-backed boosters are lightweight seats that may or may not anchor the seat of the car. The back has a curved headrest that can protect against head and neck injuries in a car accident. The headrest is adjustable, so you can raise it as your child grows. There are belt-positioning loops at the base of the headrest that you can use to make sure the shoulder belt sits properly across your child's chest.
Backless boosters. Some high-backed boosters have removable backs, so they convert to a backless seat. Your child is ready for a backless booster when their shoulders come up above the belt positioners on a high-backed booster. Your child should be able to pull the seat belt across their body without it resting on their neck.
If you are using a front-facing car seat that converts to a booster, you can anchor it to the seat using the LATCH system. You cannot attach it using the seat belt since your child will be using the belt. If your car is not equipped with LATCH, check your car seat instruction manual or the manufacturer's website. They should have instructions on how to use a booster seat without LATCH.
A high-backed booster to backless booster may have tethers to clip it to the LATCH anchors in your car. This is not necessary for using the booster seat, but it might be convenient to have your booster seat held in one place. If you're not using LATCH, you can set the booster in the back seat where your child will sit.
To use the belt positioner on a high-backed booster, adjust the headrest to the proper height. Check the instruction manual or manufacturer's website for specific details. Once the headrest is adjusted, you can slide the seat belt through the belt positioner. Check the placement of the seat belt every time your child rides in the car. As with any car seat check the expiration date to ensure the seat was not involved in a car accident or is missing any parts.
States have specific laws about when children can stop using booster seats. Some states base it on the age of the child. Others have height and weight guidelines.
The CDC recommends that children use booster seats until the seat belt fits without the extra height of the booster. Proper fit means the lap belt sits across the child's upper thighs, and the shoulder belt is across the center of the shoulder and chest.
Typically, the seat belt fits properly on children when they are 4'9" tall. Kids may not reach that height until they are nine years old or older. Even if a child outgrows the need for a booster seat, they should keep riding in the back seat until they are 13 years old.
If you have questions about booster seats, ask your pediatrician. They can help you keep your kids safe in the car.