Stage 3: Booster Seat

Is My Child Ready for Stage 3?

The law requires booster seats for children who have outgrown a child car seat but are too small for the adult seat belt.

If a child has outgrown a harnessed seat by weight or height but is not 18kg (40lbs) and developmentally ready for a booster, look for a taller, higher-weight harnessed seat.

A booster should be used until your child fits the seat belt safely.

Booster Installation Check

  • The seat belt is positioned properly over the collarbone and flat across the upper thighs while your child is sitting in his/her booster. It does not cover the belly, dig into the neck, or slip off of the shoulder.

Child Seat Belt Check

  • Your child must be able to sit up straight all of the time to be safe. This means your child does not slouch forward or lean over when they fall asleep. 

Is My Child Ready for Stage 4?

A seat belt alone can be used when children are tall enough for it to be positioned correctly and can use it properly. In Ontario, the child must be over the age of 8 years or weigh more than 36kg (80lbs) or is taller than 145cm (4’ 9”). However, height is a very important factor for maximizing the effectiveness of a seat belt, and most children don't reach this height until at least age 11.