Booster seats are often called belt-positioning booster seats because they position the vehicle’s safety belt properly on the child.  The booster makes sure that the lap belt rests on the lap, over the strong hip bones – and nowhere near the soft belly.  The booster also makes sure that the shoulder belt rests between the shoulder and the neck – so the child is comfortable and won’t put the belt behind her back or under her arm. When a child rides on a booster, he must use the vehicle’s shoulder AND lap belt across them. 

There are two types of booster seats: high back boosters and no-back boosters

Kids, especially younger ones, are safer in a 5-point harness.  Don’t rush to “graduate” your child to a booster seat.   Kids who are AT LEAST 40 pounds AND AT LEAST 3-4 years old can start riding on boosters.  Kids should ride on a booster UNTIL they can pass the 5-step-test (usually age 8-10), which you can see below.

 Ask yourself these questions and answer Yes or No.

The 5-Step Test
 

1. Does the child sit all the way back against the auto seat?
2. Do the child's knees bend comfortably at the edge of the auto seat?
3. Does the belt cross the shoulder between the neck and arm?
4. Is the lap belt as low as possible, touching the thighs?
5. Can the child stay seated like this for the whole trip?

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If you answer  "no" to any of these questions, your child STILL needs a booster seat to make both the shoulder belt and the lap belt fit right and to keep them safest.

Why should kids ride in a booster?

Because the vehicle seat is too big and a child’s bone structure is too small and underdeveloped to keep the safety belt in the proper place during a crash. A 4-8 year old child riding in a booster is 59% less likely to be injured in a crash than a 4-8 year old wearing a safety belt alone.