What Are the Height & Weight Restrictions for Child Booster Seats in Ontario?

According to the Ministry of Transportation of Ontario, a booster seat protects your child 3.5 times more effectively than a seat belt alone 1. Seat belts in vehicles are not made for children and will not protect them in the event of a crash. Once your child outgrows his harnessed car seat, he will need to use a booster seat until he meets the minimum requirements for a normal seat belt. A booster seat works by raising your child so that the vehicle's seat belt fits him better.

Minimum Requirements

Once your child reaches 4 years of age and weighs at least 18.1 Kilogram, she can begin to use a booster seat. The seat raises her slightly so that the seat belt hits her body in the right places. Without a booster seat, the seat belt tends to hit too high on the stomach and comes down over the neck instead of the shoulder. The penalty in Ontario for driving without your child properly secured in your vehicle is a £71 fine and two demerit points on your driving record.

Requirements to Stop Using Booster

Once your child turns 8 years of age, reaches 36.3 Kilogram in weight or measures 4 feet 9 inches tall, he no longer requires a booster seat by law in Ontario. Make sure the seat belt lies flat across his shoulders and the middle of his chest, and that the lap portion crosses his hips and not his stomach. Children should remain in the rear seat of your vehicle until they are at least 13 years old.

Recommendations for Increased Safety

Despite the minimum requirements of the law, the Canadian Paediatric Society recommends that you keep your child in a harnessed forward-facing seat as long as possible. Many harnessed seats are now available that will allow your child to stay harnessed until at least 29.5 Kilogram. The CPS also recommends that you keep your child in a booster seat until she is 4 feet 9 inches and 36.3 Kilogram, with no mention of an age threshold. Some children do not reach these height and weight milestones until age 12.

Types of Boosters

Booster seats come in two basic styles -- high back or low back. High back booster seats have a seat back and headrest. They also provide extra head and neck protection for vehicles without head restraints. Low back boosters are more compact and portable, and are suitable for use in vehicles with high seat backs and adjustable head restraints.