You can stop using a car booster seat when your child can pass the "5-Step Test" for proper seat belt fit, which typically occurs when they are between 8 and 12 years old, around 4 feet 9 inches (57 inches) tall, and weigh between 80 and 100 pounds. The key factor is not age but physical size, ensuring the vehicle's seat belt rests correctly on their body without a booster. Rushing this transition can compromise safety in a crash.
The 5-Step Test is the industry-standard method to determine if a child is ready. Have your child sit against the vehicle seat back with their knees bent naturally at the seat's edge. Then, check these five points:
- Does the child sit all the way back against the auto seat?
- Do the child's knees bend comfortably at the edge of the seat?
- Does the lap belt sit low across the upper thighs, touching the hips?
- Does the shoulder belt cross the middle of the shoulder and chest?
- Can the child stay seated like this for the entire trip?
If the answer to any of these is "no," they still need a booster. The lap belt riding up on the soft abdomen or the shoulder belt cutting across the neck are significant injury risks. Most children need a booster seat until they are at least 4'9" tall, which many kids don't reach until they are 10 or 11 years old. Always follow your state's specific laws, which set minimum requirements, but the 5-Step Test is the best practice for safety.
| State | Booster Seat Law Minimum (Typical) | Notes |
|---|
| California | 8 years old or 4'9" tall | Whichever comes first |
| Texas | 8 years old or 4'9" tall | Whichever comes first |
| New York | 8 years old | Law does not specify height |
| Florida | 4-5 years old (varies) | Less strict; emphasizes best practices |
| National Highway Traffic Safety Administration (NHTSA) Recommendation | 4'9" tall (57 inches) | Based on the 5-Step Test, not age |
