Road Rules

Child Safety Seat Laws in Missouri

3 min read

Missouri law requires that children be properly restrained in motor vehicles using federally approved safety seats or belts based on age, weight, and height. These laws are designed to protect young passengers and reduce injury risk in the event of a crash.

Age and Size-Based Restraint Requirements

Under 4 Years Old or Under 40 Pounds

Children who are younger than 4 years old or weigh less than 40 pounds must be secured in an appropriate child safety seat. This typically means a rear-facing or forward-facing car seat with a harness.

Ages 4–7, Weighing at Least 40 Pounds

Children between 4 and 7 years old who weigh at least 40 pounds but are less than 80 pounds or shorter than 4 feet 9 inches must use a booster seat. The booster must position the seat belt correctly across the child’s chest and lap.

Ages 8 and Up, or Over 80 Pounds or 4’9” Tall

Once a child reaches age 8, weighs 80 pounds, or is at least 4’9” tall, they may use the vehicle’s seat belt without a booster—if the belt fits properly across the hips and shoulder.

Proper Use and Installation

The Missouri Department of Transportation (MoDOT) urges caregivers to follow manufacturer instructions for car seat installation and use. Most injuries occur due to incorrect use of safety seats. Certified Child Passenger Safety Technicians can help ensure your seat is installed properly. Visit MoDOT's website for resources and local inspection stations.

Pickup Truck Exception

If a child is being transported in a vehicle without a rear seat, such as a pickup truck, a front-seat installation is permitted only if the airbag is deactivated or the child seat is designed to be used in front seats. Rear-facing seats must never be placed in front of an active airbag.

Enforcement and Penalties

Violating Missouri’s child restraint laws can result in a $50 fine plus court costs. The fine may be waived if proof of acquisition of a proper child safety seat is presented to the court.

Exemptions

Exemptions include:

Children being transported in public carriers (e.g., school buses or taxis)
Children with documented medical conditions making seat use unsafe (must carry physician's certification)

Additional Resources

Parents should familiarize themselves with broader driving safety rules, especially when traveling through rural or high-speed areas. For more information on Missouri traffic rules, explore these resources:

Always ensure that any safety seat used is not expired, has never been in a crash, and meets current federal safety standards.