The law in Ontario says that you must have your baby in a rear-facing car seat from birth to at least 9 kg (20 lbs.).
However, it is best to keep your child in a rear-facing car seat for as long as possible. Some rear-facing car seats are for children that weigh up to 20 kg (50 lbs.). It is okay for your child’s legs to touch the back of your vehicle's seat as long as your child is still below the weight and height limits of the child car seat.
How to install your rear-facing car seat
Always check your vehicle's manual and car seat's user guide for how to install your child's car seat. To ensure a proper recline, use the level indicator found on the car seat. Always check for movement at the belt path. Make sure the car seat does not move more than 2.5 cm (1") from side to side or from front to back.
How to buckle up your child
Make sure the shoulder harness straps are at or just below your baby's shoulders and that the chest clip is at armpit level. Ensure the straps are straight and do not twist or fold. Use the “Pinch Test” to ensure that the harness is properly secured. To do this, you need to pinch the harness vertically, at your child’s shoulders. If you can pinch and hold the harness, then it needs to be tightened.
For information on the positioning of the handle on your child's car seat, check your car seat's user guide or speak with the manufacturer.
Safety Drives Us: Rear-facing Child Car Seat (video) available in multiple languages