One of the most common safety oversights we see is children being kept in a car seat after they’ve outgrown its limits. That’s why our fourth tip for Child Safety Week is all about knowing your car seat's height and weight restrictions — and understanding how they change as the seat does.
Why it matters
Car seats are rigorously tested for safety, but only within the parameters they’re designed for. That means if a child exceeds the stated height or weight limit, the seat may no longer protect them properly in a crash. Straps may sit in the wrong place, harness tension may be inadequate, and the seat structure itself may be compromised under stress.
It’s not just about age
Age is a general guideline, but height and weight are the critical factors. Your child may look small or seem fine in a seat, but the only way to ensure they’re safe is to:
- Regularly weigh and measure your child
- Compare their stats to the seat’s limits in the manual
- Consider whether the seat is being used in rear-facing, forward-facing, or high-back booster mode
Pay close attention with multistage seats
Multistage seats (sometimes called 2-in-1 or 3-in-1 seats) are designed to grow with your child. But each stage will have its own limits. For example:
- Rear-facing mode may be approved up to 18kg, 25kg, or 36kg depending on the model, with height limits of either 105cm or 125cm
- Forward-facing with a harness might be limited to anything between 18kg - 22kg
- Booster mode typically starts around 100cm and goes up to 150cm or more
Make sure you’re not just relying on your child fitting visually — double-check they’re within the approved range for the mode you’re using.
Watch for signs of outgrowing:
- Harness straps sitting below the shoulders in forward-facing mode or dipping more than 2cm below in rear-facing seats
- The top of your child’s head reaching the top of the seat shell in infant carriers
- Your child exceeding the maximum stated weight or height
Need help?
Not sure whether your child is still within the limits of their current seat? Our expert team is always happy to help. Send us your seat details and your child’s height and weight, and we’ll talk you through your options.
It’s Child Safety Week — and sharing knowledge like this keeps kids safer every day.